The Characteristics of Parabolas – Points of Interest
Opens Up
x-int
Axis of Sym
x=1

Min (-1,-3)

Axis of Sym
x=1

a) Up if a>o
b) Down if a<o

Quadratic equations in
in this form:
f ( x ) ax 2 bx c

y-int 2) Vertex

Vertex
Max (-1,5)

a) Minimum if a>o

b) Maximum if a<o
3) x-intercepts

a) Where f(x) =0
4) y-intercepts

y-int

Opens
Down

1) Open Up or Down?

a) Where x=0
5) Axis of Symmetry

x-int

a) The x-value at the
vertex

f (x)

a( x

h )2

k
Solving Quadratic
equations in this form:

ax

2

bx

c

0, a

1) Factoring
2) Square Root Property
2
If u
d,
then u

d

3) The Quadratic Formula
x

b

b

2

2a

4ac

0
Which
one to
use?
Ch 11.2 #2,6,9,18

x2

#2

8 x 15

0

a 1b
,
x
x
x

Quadratic equations in
this form:
ax 2 bx c 0, a 0

8, c 15

( 8)

2

8

1) Factoring

4 • 1 • 15

2) Square Root Property

If u 2

2 1
8
-8

then u

64 60
2
4

x

4 1
3 or

d

3) The Quadratic
Formula

2

8 2
x
2
x
4 1
x -5,-3

d,

x

4 1

5

b

b

2

2a

4ac
Ch 11.2 #2,6,9,18

#6

x2

5 x 10

a 1b
,
( 5)

x

5

10
2

4 • 1 • -10

1) Factoring
2) Square Root Property

If u 2

2 1
5

x
x

5,c

0

Quadratic equations in
this form:
ax 2 bx c 0, a 0

-5

25 40
2

d,

then u
3) The Quadratic
Formula

65
2

d

x

b

b

2

2a

4ac
Ch 11.2 #2,6,9,18

# 9 6x

6x
a

2

2x 1

2x 1 0

6, b
( -2)

x

x

2

2, c
-2

2

4
12

24

1) Factoring
2) Square Root Property

If u 2

1
4 • 6 • -1

2 6

2

Quadratic equations in
this form:
ax 2 bx c 0, a 0

2

28
12
2 2 7
12

d,

then u

d

3) The Quadratic
Formula

x

2(1
7)
2 6

b

b

2

2a

1

7
6

4ac
Ch 11.2 #2,6,9,18

Quadratic equations in
this form:
ax 2 bx c 0, a 0

#18 2x( x 4) 3x 3
2x 2 8 x 3 x 3
2x
a
x

x

x

2

5x 3

2, b
(5 )

0

5, c
5

2

1) Factoring
2) Square Root Property

If u 2

3

then u

4• 2 • 3

6
4

25 24
4

3
or x
2

5

5 1
4

1
4
4
4

1

d

3) The Quadratic
Formula

2 2
5

d,

x

x

3
,
2

b

b

2

2a

1

4ac
Ch 11.2 #42,43,46
# 42

4x-1

2

15

4 x -1
4x
x

15

1

Which one
to use?

Quadratic equations in
this form:
ax 2 bx c 0, a 0
1) Factoring
2) Square Root Property

If u 2

15

1

15
4

d,

then u

d

3) The Quadratic
Formula

x

b

b

2

2a

4ac
Ch 11.2 #42,43,46

1
x

# 43

3x x+2

3 x

2

1

1
3 LCD 3 x x

x 2
1
x

1
x 2

3x

3x 6 3x

x

2

1
3

4x 6

x x

x

2

0

Quadratic equations in
this form:
ax 2 bx c 0, a 0
2
1) Factoring
2) Square Root Property

If u 2

d,

then u

2

2x

d

3) The Quadratic
Formula

x

b

b

2

2a

4ac
Ch 11.2 #42,43,46

x

2

4x 6

a 1b
,

Which one
to use?

0

4, c

Quadratic equations in
this form:
ax 2 bx c 0, a 0
1) Factoring
2) Square Root Property

6

If u 2

# 46

7x x-2

7x2 14x

3 2 x

then u

4

3 2x 8

7x

12x 5

0 Which one
to use?

d

3) The Quadratic
Formula

x
2

d,

b

b

2

2a

4ac
Writing an equation when
solutions are given
Ch 11.2 #48,54

# 48
x

2,6
2 or x

Quadratic equations in
this form:
ax 2 bx c 0, a 0
1) Factoring
2) Square Root Property

6

If u 2

Work backwards
x

2
x

x

2

0 or x - 6
2 x 6

4x 12

0

0

0

d,

then u

d

3) The Quadratic
Formula

x

b

b

2

2a

4ac
Writing an equation when
solutions are given
Ch 11.2 #48,54
# 54
x

3, 3

3

0 or x

3

0

Quadratic equations in
this form:
ax 2 bx c 0, a 0
1) Factoring
2) Square Root Property

If u 2

Work backwards
x

3

x

3 =0

then u

x

3

0

d

3) The Quadratic
Formula

x

2

d,

b

b

2

2a

4ac
The Shape of the Graph of a
Quadratic Equation:
a Parabola

Quadratic equations in
in this form:
f ( x ) ax 2 bx c
f (x)

a( x

h )2

k
The Characteristics of Parabolas – Points of Interest
Opens Up
x-int
Axis of Sym
x= -1

Min (-1,-3)

Axis of Sym
x= -1

a) Up if a>o
b) Down if a<o

Quadratic equations in
in this form:
f ( x ) ax 2 bx c

y-int 2) Vertex

Vertex
Max (-1,5)

a) Minimum if a>o

b) Maximum if a<o
3) x-intercepts

a) Where f(x) =0
4) y-intercepts

y-int

Opens
Down

1) Open Up or Down?

a) Where x=0
5) Axis of Symmetry

x-int

a) The x-value at the
vertex

f (x)

a( x

h )2

k
Graphing Parabolas in form
Ch 11.3 #10,11,14,16 Find the Vertex
#10

f ( x ) -3 x - 2
h 2
vertex

k

2

12

(2,12)

12

ax 2

bx

c

a( x
Rules

h )2

k

f (x)
f (x)

1) Open Up or Down?

a) Up if a>o
b) Down if a<o
2) Find the Vertex

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a

for f ( x )

3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
Graphing Parabolas in form
Ch 11.3 #10,11,14,16 Find the Vertex
#11 f ( x ) -2 x 1

2

1
f ( x ) -2 x ( 1)

ax 2

bx

c

a( x
Rules

h )2

k

f (x)
f (x)

1) Open Up or Down?

a) Up if a>o
b) Down if a<o

5
2

h
1 k 5
vertex
(-1,5)

5

2) Find the Vertex

for f ( x )

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
Ch 11.3 #10,11,14,16 Find the Vertex
#14

f ( x ) 3 x 2 12 x 1
12
a 3 b

( 12)
2(3)
f ( 2)
Vertex

3 2

12
6
2

1) Open Up or Down?

a) Up if a>o
b) Down if a<o

2

12 2

b
2 ,
2a

Rules

11
f ( 2)

1 12 24 1

11

2) Find the Vertex

for f ( x )

k

for f ( x )

a 2 b
ax bx c
b
b ,f
2a
2a

a( x h )2
Vertex= ( h , k )

Vertex

3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
Ch 11.3 #10,11,14,16 Find the Vertex
#16

2x 2 8x 1
2 b 8

f (x)
a

(8 )
2( 2)
f ( 2)
Vertex

8
4

2 2

2

b
2 ,
2a

Rules
1) Open Up or Down?

a) Up if a>o
b) Down if a<o

2

8 2
f (7 )
2

1

8 16 1 7

2) Find the Vertex

for f ( x )

k

for f ( x )

a 2 b
ax bx c
b
b ,f
2a
2a

a( x h )2
Vertex= ( h , k )

Vertex

3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
Ch 11.3 #18,34 Graph Opens
2
#18
f x
x 1
2 up
a=1 >0
h 1 k
2
vertex

x-intercepts

y-intercepts

(1

2,0) (1

2,0)

f (0 )

1) Open Up or Down?

a) Up if a>o
b) Down if a<o

(1, 2)

2

x 1
2 0
2
x 1
2
x 1 ± 2
x 1± 2

Rules

2

0 1
2
2
1
2
1 2
1

(0, 1)

2) Find the Vertex

for f ( x )

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

x

h or x

1

b
2a
# 34

6 4 x x 2 Opens
x 2 4 x 6 up >0
a=1
4
a 1 b

f x
f x

Vertex

4

b

2(1)

2(a )
f ( 2)
Vertex

4
2

2

2

4 2

b
2a

2 ,

Rules
1) Open Up or Down?

a) Up if a>o
b) Down if a<o
2) Find the Vertex

2

for f ( x )

6
f (2 )

4 8 6 2

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
6 4 x x 2 Opens
x 2 4 x 6 up
a=1 >0
Vertex = (2,2)

# 34

f x
f x

x-intercepts
x

2

4x

6

y-intercepts

0

Use Quad. Form.
OR
Look at the graph
so far....

No x intercepts

f (0)

0

2

6

(0,6)

4(0) 6

Rules
1) Open Up or Down?

a) Up if a>o
b) Down if a<o
2) Find the Vertex

for f ( x )

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

x

h or x

2

b
2a
Finding Minimum and Maximum
Ch 11.3 #60

Definition

A person standing close to the edge
on the top of a 200-foot building
throws a baseball vertically upward.
The quadratic function
s (t )

16t 2

64t

200

If parabola opens………

a) Up (a>o)
Vertex = Min

b) Down (a<o)
Vertex = Max

models the ball’s height above the
ground, s(t), in feet, t seconds after it Rules
1) Determine what needs to
was thrown.
be maximized or
a) After how many seconds does the ball
reach max height? What is the max height?
b) How many seconds does it take until the
ball finally hits the ground?
c) Find s(0) and describe what it means
d) Use results to graph the parabola

minimized
2) Express quantity as
function

3) Rewrite in form:

f (x)

ax 2

bx c

4) Calculate Max or
Min by finding the
vertex
Max point…

Vertex = (t, s(t))

s (t )

16t 2

a

is the Vertex

64t

200

16 b

64

Feet from ground
at max

Seconds it took to
reach max
a) After how many seconds
does the ball reach max
height? What is the max
height?
Find the vertex to find max
time, t, and max height, s(t)

200 ft

Vertex

Vertex

b
64 , s
16)
2( a
2 sec ,

b
2a

s(2)
Max point…

MAX at (2 sec, s(t))feet)
Vertex = (t, 264

s (t )

16t 2

a

is the Vertex

64t

200

16 b

64

a) After how many seconds
does the ball reach max
height? What is the max
height?
Vertex

s( 2 )
s ( 2)

200 ft

s ( 2)

2 sec , 264 (2)
s feet
16( 2 )2

64( 2 ) 200

64 128 200
264 feet

It took 2 seconds to reach a
maximum height of 264 feet
Max point…

MAX at (2 sec, 264 feet)

16t 2

s (t )

a

is the Vertex

64t

200

16 b

64

b) How many seconds does it
take until the ball finally hits
the ground?

s(t)

16t 2
Factor out -2
8t 2

0

64t

200

32t 100

0
0

Use Quadratic Formula to slove

200 ft
What is the height , s(t) , when
the ball hits the ground?

s(t)

0
Max point…

MAX at (2 sec, 264 feet)

s (t )

16t 2

a

is the Vertex

64t

200

16 b

64

b) How many seconds does it
take until the ball finally hits
the ground?

8t 2 32t 100 0
32 c
a 8 b

t

( 32) ±

t

32

32

2

100

4(8)( 100)

2(8)
1024 3200
16

200 ft
What is the height , s(t) , when
the ball hits the ground?

s(t)

0
Max point…

MAX at (2 sec, 264 feet)

s (t )

16t 2

a

is the Vertex

64t

200

16 b

64

b) How many seconds does it
take until the ball finally hits
the ground?

8t 2 32t 100 0
32 c
a 8 b

t

( 32) ±

t

200 ft

32

2

4(8)( 100)

2(8)
32
1024 3200
16
32 64.99
16

6.1 seconds

100
Max point…

MAX at (2 sec, 264 feet)

s (t )

16t 2

a

is the Vertex

64t

200

16 b

64

c) Find s(0) and describe what
it means

t =0 means zero seconds
Where is the baseball at zero
seconds?

s (0 )
s (0 )

200 ft

16(0)2

64(0) 200

200 feet

The ball is in the thrower’s
hand at the top of the
building, 200 feet up.
d) Use results to graph the parabola

s (t )
Vertex

16t 2

64t

200 Opens down

2, 264

a=-16 <0

x-intercepts

Set t=0,
find s(0)
s(o)= 200

1) Open Up or Down?

a) Up if a>o
b) Down if a<o

y-intercepts

Set s(t) =0,
solve for t
t = 6.1

Rules

2) Find the Vertex

for f ( x )

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

Set f(x) =0, solve for x
4) Find y-intercepts

Set x=0, find f(0)
5) Axis of Symmetry

x

h or x

b
2a
d) Use results to graph the parabola

16t 2

s (t )

64t

200 Opens down

a=-16 <0

2, 264

Vertex

x-intercepts

Set t=0,
find s(0)
s(o)= 200

1) Open Up or Down?

a) Up if a>o
b) Down if a<o

y-intercepts

Set s(t) =0,
solve for t
t = 6.1

Rules

H
e
i
g
h
t

250
200

2) Find the Vertex

for f ( x )

a( x h )2 k
Vertex= ( h , k )
for f ( x ) a 2 b
ax bx c
b
b ,f
Vertex
2a
2a
3) Find x-intercepts

150

Set f(x) =0, solve for x
4) Find y-intercepts

100

Set x=0, find f(0)

50
2

5) Axis of Symmetry
4

6

Time

x

h or x

b
2a
•Tonight’s Lecture portion Ch 11.2 & 11.3: •DONE
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The Characteristics of Parabolas – Points of Interest
Opens Up
x-int
Axis of Sym
x=1

Min (-1,-3)

Axis of Sym
x=1

a) Up if a>o
b) Down if a<o

Quadratic equations in
in this form:
f ( x ) ax 2 bx c

y-int 2) Vertex

Vertex
Max (-1,5)

a) Minimum if a>o

b) Maximum if a<o
3) x-intercepts

a) Where f(x) =0
4) y-intercepts

y-int

Opens
Down

1) Open Up or Down?

a) Where x=0
5) Axis of Symmetry

x-int

a) The x-value at the
vertex

f (x)

a( x

h )2

k

Ch11.2&3(1)

  • 1.
    The Characteristics ofParabolas – Points of Interest Opens Up x-int Axis of Sym x=1 Min (-1,-3) Axis of Sym x=1 a) Up if a>o b) Down if a<o Quadratic equations in in this form: f ( x ) ax 2 bx c y-int 2) Vertex Vertex Max (-1,5) a) Minimum if a>o b) Maximum if a<o 3) x-intercepts a) Where f(x) =0 4) y-intercepts y-int Opens Down 1) Open Up or Down? a) Where x=0 5) Axis of Symmetry x-int a) The x-value at the vertex f (x) a( x h )2 k
  • 2.
    Solving Quadratic equations inthis form: ax 2 bx c 0, a 1) Factoring 2) Square Root Property 2 If u d, then u d 3) The Quadratic Formula x b b 2 2a 4ac 0 Which one to use?
  • 3.
    Ch 11.2 #2,6,9,18 x2 #2 8x 15 0 a 1b , x x x Quadratic equations in this form: ax 2 bx c 0, a 0 8, c 15 ( 8) 2 8 1) Factoring 4 • 1 • 15 2) Square Root Property If u 2 2 1 8 -8 then u 64 60 2 4 x 4 1 3 or d 3) The Quadratic Formula 2 8 2 x 2 x 4 1 x -5,-3 d, x 4 1 5 b b 2 2a 4ac
  • 4.
    Ch 11.2 #2,6,9,18 #6 x2 5x 10 a 1b , ( 5) x 5 10 2 4 • 1 • -10 1) Factoring 2) Square Root Property If u 2 2 1 5 x x 5,c 0 Quadratic equations in this form: ax 2 bx c 0, a 0 -5 25 40 2 d, then u 3) The Quadratic Formula 65 2 d x b b 2 2a 4ac
  • 5.
    Ch 11.2 #2,6,9,18 #9 6x 6x a 2 2x 1 2x 1 0 6, b ( -2) x x 2 2, c -2 2 4 12 24 1) Factoring 2) Square Root Property If u 2 1 4 • 6 • -1 2 6 2 Quadratic equations in this form: ax 2 bx c 0, a 0 2 28 12 2 2 7 12 d, then u d 3) The Quadratic Formula x 2(1 7) 2 6 b b 2 2a 1 7 6 4ac
  • 6.
    Ch 11.2 #2,6,9,18 Quadraticequations in this form: ax 2 bx c 0, a 0 #18 2x( x 4) 3x 3 2x 2 8 x 3 x 3 2x a x x x 2 5x 3 2, b (5 ) 0 5, c 5 2 1) Factoring 2) Square Root Property If u 2 3 then u 4• 2 • 3 6 4 25 24 4 3 or x 2 5 5 1 4 1 4 4 4 1 d 3) The Quadratic Formula 2 2 5 d, x x 3 , 2 b b 2 2a 1 4ac
  • 7.
    Ch 11.2 #42,43,46 #42 4x-1 2 15 4 x -1 4x x 15 1 Which one to use? Quadratic equations in this form: ax 2 bx c 0, a 0 1) Factoring 2) Square Root Property If u 2 15 1 15 4 d, then u d 3) The Quadratic Formula x b b 2 2a 4ac
  • 8.
    Ch 11.2 #42,43,46 1 x #43 3x x+2 3 x 2 1 1 3 LCD 3 x x x 2 1 x 1 x 2 3x 3x 6 3x x 2 1 3 4x 6 x x x 2 0 Quadratic equations in this form: ax 2 bx c 0, a 0 2 1) Factoring 2) Square Root Property If u 2 d, then u 2 2x d 3) The Quadratic Formula x b b 2 2a 4ac
  • 9.
    Ch 11.2 #42,43,46 x 2 4x6 a 1b , Which one to use? 0 4, c Quadratic equations in this form: ax 2 bx c 0, a 0 1) Factoring 2) Square Root Property 6 If u 2 # 46 7x x-2 7x2 14x 3 2 x then u 4 3 2x 8 7x 12x 5 0 Which one to use? d 3) The Quadratic Formula x 2 d, b b 2 2a 4ac
  • 10.
    Writing an equationwhen solutions are given Ch 11.2 #48,54 # 48 x 2,6 2 or x Quadratic equations in this form: ax 2 bx c 0, a 0 1) Factoring 2) Square Root Property 6 If u 2 Work backwards x 2 x x 2 0 or x - 6 2 x 6 4x 12 0 0 0 d, then u d 3) The Quadratic Formula x b b 2 2a 4ac
  • 11.
    Writing an equationwhen solutions are given Ch 11.2 #48,54 # 54 x 3, 3 3 0 or x 3 0 Quadratic equations in this form: ax 2 bx c 0, a 0 1) Factoring 2) Square Root Property If u 2 Work backwards x 3 x 3 =0 then u x 3 0 d 3) The Quadratic Formula x 2 d, b b 2 2a 4ac
  • 12.
    The Shape ofthe Graph of a Quadratic Equation: a Parabola Quadratic equations in in this form: f ( x ) ax 2 bx c f (x) a( x h )2 k
  • 13.
    The Characteristics ofParabolas – Points of Interest Opens Up x-int Axis of Sym x= -1 Min (-1,-3) Axis of Sym x= -1 a) Up if a>o b) Down if a<o Quadratic equations in in this form: f ( x ) ax 2 bx c y-int 2) Vertex Vertex Max (-1,5) a) Minimum if a>o b) Maximum if a<o 3) x-intercepts a) Where f(x) =0 4) y-intercepts y-int Opens Down 1) Open Up or Down? a) Where x=0 5) Axis of Symmetry x-int a) The x-value at the vertex f (x) a( x h )2 k
  • 14.
    Graphing Parabolas inform Ch 11.3 #10,11,14,16 Find the Vertex #10 f ( x ) -3 x - 2 h 2 vertex k 2 12 (2,12) 12 ax 2 bx c a( x Rules h )2 k f (x) f (x) 1) Open Up or Down? a) Up if a>o b) Down if a<o 2) Find the Vertex a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a for f ( x ) 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 15.
    Graphing Parabolas inform Ch 11.3 #10,11,14,16 Find the Vertex #11 f ( x ) -2 x 1 2 1 f ( x ) -2 x ( 1) ax 2 bx c a( x Rules h )2 k f (x) f (x) 1) Open Up or Down? a) Up if a>o b) Down if a<o 5 2 h 1 k 5 vertex (-1,5) 5 2) Find the Vertex for f ( x ) a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 16.
    Ch 11.3 #10,11,14,16Find the Vertex #14 f ( x ) 3 x 2 12 x 1 12 a 3 b ( 12) 2(3) f ( 2) Vertex 3 2 12 6 2 1) Open Up or Down? a) Up if a>o b) Down if a<o 2 12 2 b 2 , 2a Rules 11 f ( 2) 1 12 24 1 11 2) Find the Vertex for f ( x ) k for f ( x ) a 2 b ax bx c b b ,f 2a 2a a( x h )2 Vertex= ( h , k ) Vertex 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 17.
    Ch 11.3 #10,11,14,16Find the Vertex #16 2x 2 8x 1 2 b 8 f (x) a (8 ) 2( 2) f ( 2) Vertex 8 4 2 2 2 b 2 , 2a Rules 1) Open Up or Down? a) Up if a>o b) Down if a<o 2 8 2 f (7 ) 2 1 8 16 1 7 2) Find the Vertex for f ( x ) k for f ( x ) a 2 b ax bx c b b ,f 2a 2a a( x h )2 Vertex= ( h , k ) Vertex 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 18.
    Ch 11.3 #18,34Graph Opens 2 #18 f x x 1 2 up a=1 >0 h 1 k 2 vertex x-intercepts y-intercepts (1 2,0) (1 2,0) f (0 ) 1) Open Up or Down? a) Up if a>o b) Down if a<o (1, 2) 2 x 1 2 0 2 x 1 2 x 1 ± 2 x 1± 2 Rules 2 0 1 2 2 1 2 1 2 1 (0, 1) 2) Find the Vertex for f ( x ) a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x x h or x 1 b 2a
  • 19.
    # 34 6 4x x 2 Opens x 2 4 x 6 up >0 a=1 4 a 1 b f x f x Vertex 4 b 2(1) 2(a ) f ( 2) Vertex 4 2 2 2 4 2 b 2a 2 , Rules 1) Open Up or Down? a) Up if a>o b) Down if a<o 2) Find the Vertex 2 for f ( x ) 6 f (2 ) 4 8 6 2 a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 20.
    6 4 xx 2 Opens x 2 4 x 6 up a=1 >0 Vertex = (2,2) # 34 f x f x x-intercepts x 2 4x 6 y-intercepts 0 Use Quad. Form. OR Look at the graph so far.... No x intercepts f (0) 0 2 6 (0,6) 4(0) 6 Rules 1) Open Up or Down? a) Up if a>o b) Down if a<o 2) Find the Vertex for f ( x ) a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x x h or x 2 b 2a
  • 21.
    Finding Minimum andMaximum Ch 11.3 #60 Definition A person standing close to the edge on the top of a 200-foot building throws a baseball vertically upward. The quadratic function s (t ) 16t 2 64t 200 If parabola opens……… a) Up (a>o) Vertex = Min b) Down (a<o) Vertex = Max models the ball’s height above the ground, s(t), in feet, t seconds after it Rules 1) Determine what needs to was thrown. be maximized or a) After how many seconds does the ball reach max height? What is the max height? b) How many seconds does it take until the ball finally hits the ground? c) Find s(0) and describe what it means d) Use results to graph the parabola minimized 2) Express quantity as function 3) Rewrite in form: f (x) ax 2 bx c 4) Calculate Max or Min by finding the vertex
  • 22.
    Max point… Vertex =(t, s(t)) s (t ) 16t 2 a is the Vertex 64t 200 16 b 64 Feet from ground at max Seconds it took to reach max a) After how many seconds does the ball reach max height? What is the max height? Find the vertex to find max time, t, and max height, s(t) 200 ft Vertex Vertex b 64 , s 16) 2( a 2 sec , b 2a s(2)
  • 23.
    Max point… MAX at(2 sec, s(t))feet) Vertex = (t, 264 s (t ) 16t 2 a is the Vertex 64t 200 16 b 64 a) After how many seconds does the ball reach max height? What is the max height? Vertex s( 2 ) s ( 2) 200 ft s ( 2) 2 sec , 264 (2) s feet 16( 2 )2 64( 2 ) 200 64 128 200 264 feet It took 2 seconds to reach a maximum height of 264 feet
  • 24.
    Max point… MAX at(2 sec, 264 feet) 16t 2 s (t ) a is the Vertex 64t 200 16 b 64 b) How many seconds does it take until the ball finally hits the ground? s(t) 16t 2 Factor out -2 8t 2 0 64t 200 32t 100 0 0 Use Quadratic Formula to slove 200 ft What is the height , s(t) , when the ball hits the ground? s(t) 0
  • 25.
    Max point… MAX at(2 sec, 264 feet) s (t ) 16t 2 a is the Vertex 64t 200 16 b 64 b) How many seconds does it take until the ball finally hits the ground? 8t 2 32t 100 0 32 c a 8 b t ( 32) ± t 32 32 2 100 4(8)( 100) 2(8) 1024 3200 16 200 ft What is the height , s(t) , when the ball hits the ground? s(t) 0
  • 26.
    Max point… MAX at(2 sec, 264 feet) s (t ) 16t 2 a is the Vertex 64t 200 16 b 64 b) How many seconds does it take until the ball finally hits the ground? 8t 2 32t 100 0 32 c a 8 b t ( 32) ± t 200 ft 32 2 4(8)( 100) 2(8) 32 1024 3200 16 32 64.99 16 6.1 seconds 100
  • 27.
    Max point… MAX at(2 sec, 264 feet) s (t ) 16t 2 a is the Vertex 64t 200 16 b 64 c) Find s(0) and describe what it means t =0 means zero seconds Where is the baseball at zero seconds? s (0 ) s (0 ) 200 ft 16(0)2 64(0) 200 200 feet The ball is in the thrower’s hand at the top of the building, 200 feet up.
  • 28.
    d) Use resultsto graph the parabola s (t ) Vertex 16t 2 64t 200 Opens down 2, 264 a=-16 <0 x-intercepts Set t=0, find s(0) s(o)= 200 1) Open Up or Down? a) Up if a>o b) Down if a<o y-intercepts Set s(t) =0, solve for t t = 6.1 Rules 2) Find the Vertex for f ( x ) a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts Set f(x) =0, solve for x 4) Find y-intercepts Set x=0, find f(0) 5) Axis of Symmetry x h or x b 2a
  • 29.
    d) Use resultsto graph the parabola 16t 2 s (t ) 64t 200 Opens down a=-16 <0 2, 264 Vertex x-intercepts Set t=0, find s(0) s(o)= 200 1) Open Up or Down? a) Up if a>o b) Down if a<o y-intercepts Set s(t) =0, solve for t t = 6.1 Rules H e i g h t 250 200 2) Find the Vertex for f ( x ) a( x h )2 k Vertex= ( h , k ) for f ( x ) a 2 b ax bx c b b ,f Vertex 2a 2a 3) Find x-intercepts 150 Set f(x) =0, solve for x 4) Find y-intercepts 100 Set x=0, find f(0) 50 2 5) Axis of Symmetry 4 6 Time x h or x b 2a
  • 30.
    •Tonight’s Lecture portionCh 11.2 & 11.3: •DONE •5 points for Attendance given at: •8:30 PM •Homework Assignments due by 8:30PM:•Ch 11.2 & 11.3 •Tonight’s Assignments already done? : •Turn them in BEFORE you leave •Receive 5 points for attendance •You may leave anytime AFTER the LECTURE portion •Arriving late (after 6:45 pm) AND THEN leaving early: •Receive ZERO points for attendance
  • 31.
    The Characteristics ofParabolas – Points of Interest Opens Up x-int Axis of Sym x=1 Min (-1,-3) Axis of Sym x=1 a) Up if a>o b) Down if a<o Quadratic equations in in this form: f ( x ) ax 2 bx c y-int 2) Vertex Vertex Max (-1,5) a) Minimum if a>o b) Maximum if a<o 3) x-intercepts a) Where f(x) =0 4) y-intercepts y-int Opens Down 1) Open Up or Down? a) Where x=0 5) Axis of Symmetry x-int a) The x-value at the vertex f (x) a( x h )2 k