PROBLEMS
INVOLVING
PARALLELOGRAM,
TRAPEZOID AND
OBJECTIV
ES
1. Analyze
problems
involving
parallelog
rams,
trapezoids
and kites
2. Applies tips to
consider in
solving problems
involving
parallelograms,
trapezoids and
kites
3. Show
accuracy in
solving problem
involving
parallelograms,
trapezoid and
kites
Step 1 Step 2 Step 3
Boy or Girl
Choose Boy
If the answer
is FALSE
Choose Girl
if the answer
is TRUE
If your answer is
correct, you may
take your seat,
but if your
answer is wrong,
please remain
standing until
your classmate
save you!
1. If a quadrilateral is an
isosceles trapezoid, then the
diagonals are congruent.
TRUE
2. If a quadrilateral is an isosceles
trapezoid, then the consecutive
angles are supplementary.
FALSE
3. An isosceles trapezoid is a
trapezoid with congruent
bases.
FALSE
4. If a quadrilateral is a kite, then
it has one diagonal that bisects a
pair of opposite angles.
TRUE
5. If a quadrilateral is a kite, then
its area is half the product of the
lengths of its diagonals.
TRUE
PROBLEMS
INVOLVING
PARALLELOGRAM,
TRAPEZOID AND
Tips to consider in solving problems
involving parallelograms, trapezoids and
kites:
1.Draw the quadrilateral with the given
values.
2.Analyze the problem (Think of all the
properties and theorems that could be
helpful in solving the problem).
3.Solve the problem.
Problem
#1a
Given:
1. Quadrilateral
WISH is a
parallelogram.
a. If m W = x + 15
∠
and m S = 2x + 5,
∠
what is m W?
∠
Solution
Step 1: Draw the
quadrilateral
The relationship between
∠W and S in
∠
parallelogram WISH is
that they are congruent
as they are opposite
angles. Equate the two
expressions to solve for x
and eventually the
measure of W.
∠
Step 3: Solve
the Problem
x + 15 = 2x + 5
15 – 5 = 2x - x
x = 10
Therefore,
m W = x + 15
∠
= 10 + 15
= 25o
Step 2: Analyze
the Problem
Problem
#1b
Given:
2. Parallelogram
WISH is a rectangle
and its perimeter is
62 cm. One side is 5
cm less than the
other side. What are
its dimensions and
how large is its area?
Solution
Step 1: Draw the
quadrilateral
Since it’s a rectangle, let x be
the longer side and x-5 the
other side and the opposite
sides are congruent. To find
the value of x and eventually
the dimensions, use the
formula in finding the
perimeter as this is already
given. Then, find the area
(A=LW) .
Step 3: Solve
the Problem
Step 2: Analyze
the Problem
𝑃 = 2( + )
𝐿 𝑊
62 = 2 (x – 5 + x)
62 = 2(2x - 5)
62 = 4 10
𝑥 −
62 + 10 = 4𝑥
72 = 4𝑥
= x
x = 𝟏𝟖
Step 3: Solve
the Problem
𝑃 = 2( + )
𝐿 𝑊
62 = 2 (x – 5 + x)
62 = 2(2x - 5)
62 = 4 10
𝑥 −
62 + 10 = 4𝑥
72 = 4𝑥
= x
x = 𝟏𝟖
Therefore,
the width(x) is
18cm, length(x-5)
is 13cm and the
area(L times
width) is 234 cm2
.
Problem
#2a
Given:
1. Quadrilateral POST is
an isosceles trapezoid
and ER is its midline.
a. If ST = 2x, PO = x-5
and ER = 38cm, how
long is each base?
Solution
Step 1: Draw the
quadrilateral
To find the value of
x, we need to use the
equation in finding
the midline of a
trapezoid.
ER =
Step 3: Solve
the Problem
Step 2: Analyze
the Problem
ER =
38 =
76 = 3x - 5
76 + 5 = 3x
81 = 3x
x =
x = 27
Step 3: Solve the
Problem ER =
38 =
76 = 3x - 5
76 + 5 = 3x
81 = 3x
x =
x = 27
Therefore, the bases
PO = x – 5
= 27 – 5
= 22 cm
TS = 2x
= 2(27)
= 54 cm
Problem
#2b
Given:
If m T = 2x + 5
∠
and m S= 3x-
∠
10, what is m
O?
∠
Solution
Step 1: Draw the
quadrilateral
The relationship between
∠T and S in trapezoid POST is that
∠
they are congruent. We need to
equate the given expressions to find
the value of x, eventually the m T and
∠
m O as they are supplementary.
∠
Step 2: Analyze the
Problem
Step 3: Solve the
Problem
2 + 5 = 3 10
𝑥 𝑥 −
10 + 5 = 3x-2x
x = 15
∠T = 2x + 5
=2(15) + 5
= 30 + 5
∠T = 35°
∠T + O = 180
∠
35 + O = 180
∠
∠O = 180 35
−
∠O = °
𝟏𝟒𝟓
∠T + O= 180
∠
35° + ° = 180°
𝟏𝟒𝟓
Problem
#3a
Given:
Quadrilateral LIKE
is a kite
a. is twice . If its
perimeter is 240
cm, how long is ?
Solution
Step 1: Draw the
quadrilateral
The perimeter of the kite will
be used to find the value of x
and eventually the length of .
P = 2 ( + )
Step 2: Analyze the
Problem
Step 3: Solve the
Problem
240 = 2(x + 2x)
240 = 2(3x)
240 = 6x
= x
𝒙 = 40
Therefore,
= 2x
= 2(40)
= 80 cm
Application
a 9
13
23
25
b
c
d
Direction: Choose the correct answer.
1. CDAB below is a rhombus with m ADB =
⊡ ∠
6x+ 20
and m BDC = 80
∠ 0
. What is the value of
x?
Application
a
b
c
d
Direction: Choose the correct answer.
2. Using the figure below, what is m
ABC?
∠
Application
a 5 𝑐𝑚
b
c
d
Direction: Choose the correct answer.
3. ABCD below is a parallelogram with = 3x+
⊡
5 cm, = 4x – 5 cm, and = 6x – 10 cm. What is
length of ?
11𝑐𝑚
15𝑐𝑚
20𝑐𝑚
Application
a 50𝑐𝑚
b
c
d
Direction: Choose the correct answer.
4. Using the figure below, what is the
perimeter of the parallelogram?
6 0𝑐𝑚
70𝑐𝑚
80𝑐𝑚
Application
a 3
b
c
d
Direction: Choose the correct answer.
5. HYUN below is a square with diagonal =
⊡
7x – 20 cm and = 3x + 4 cm. Find the value of
x
5
6
9

Problems involving Parallelograms, Trapezoids, and Kite.pptx

  • 1.
  • 2.
    OBJECTIV ES 1. Analyze problems involving parallelog rams, trapezoids and kites 2.Applies tips to consider in solving problems involving parallelograms, trapezoids and kites 3. Show accuracy in solving problem involving parallelograms, trapezoid and kites
  • 3.
    Step 1 Step2 Step 3 Boy or Girl Choose Boy If the answer is FALSE Choose Girl if the answer is TRUE If your answer is correct, you may take your seat, but if your answer is wrong, please remain standing until your classmate save you!
  • 4.
    1. If aquadrilateral is an isosceles trapezoid, then the diagonals are congruent. TRUE
  • 5.
    2. If aquadrilateral is an isosceles trapezoid, then the consecutive angles are supplementary. FALSE
  • 6.
    3. An isoscelestrapezoid is a trapezoid with congruent bases. FALSE
  • 7.
    4. If aquadrilateral is a kite, then it has one diagonal that bisects a pair of opposite angles. TRUE
  • 8.
    5. If aquadrilateral is a kite, then its area is half the product of the lengths of its diagonals. TRUE
  • 9.
  • 10.
    Tips to considerin solving problems involving parallelograms, trapezoids and kites: 1.Draw the quadrilateral with the given values. 2.Analyze the problem (Think of all the properties and theorems that could be helpful in solving the problem). 3.Solve the problem.
  • 11.
    Problem #1a Given: 1. Quadrilateral WISH isa parallelogram. a. If m W = x + 15 ∠ and m S = 2x + 5, ∠ what is m W? ∠ Solution Step 1: Draw the quadrilateral
  • 12.
    The relationship between ∠Wand S in ∠ parallelogram WISH is that they are congruent as they are opposite angles. Equate the two expressions to solve for x and eventually the measure of W. ∠ Step 3: Solve the Problem x + 15 = 2x + 5 15 – 5 = 2x - x x = 10 Therefore, m W = x + 15 ∠ = 10 + 15 = 25o Step 2: Analyze the Problem
  • 13.
    Problem #1b Given: 2. Parallelogram WISH isa rectangle and its perimeter is 62 cm. One side is 5 cm less than the other side. What are its dimensions and how large is its area? Solution Step 1: Draw the quadrilateral
  • 14.
    Since it’s arectangle, let x be the longer side and x-5 the other side and the opposite sides are congruent. To find the value of x and eventually the dimensions, use the formula in finding the perimeter as this is already given. Then, find the area (A=LW) . Step 3: Solve the Problem Step 2: Analyze the Problem 𝑃 = 2( + ) 𝐿 𝑊 62 = 2 (x – 5 + x) 62 = 2(2x - 5) 62 = 4 10 𝑥 − 62 + 10 = 4𝑥 72 = 4𝑥 = x x = 𝟏𝟖
  • 15.
    Step 3: Solve theProblem 𝑃 = 2( + ) 𝐿 𝑊 62 = 2 (x – 5 + x) 62 = 2(2x - 5) 62 = 4 10 𝑥 − 62 + 10 = 4𝑥 72 = 4𝑥 = x x = 𝟏𝟖 Therefore, the width(x) is 18cm, length(x-5) is 13cm and the area(L times width) is 234 cm2 .
  • 16.
    Problem #2a Given: 1. Quadrilateral POSTis an isosceles trapezoid and ER is its midline. a. If ST = 2x, PO = x-5 and ER = 38cm, how long is each base? Solution Step 1: Draw the quadrilateral
  • 17.
    To find thevalue of x, we need to use the equation in finding the midline of a trapezoid. ER = Step 3: Solve the Problem Step 2: Analyze the Problem ER = 38 = 76 = 3x - 5 76 + 5 = 3x 81 = 3x x = x = 27
  • 18.
    Step 3: Solvethe Problem ER = 38 = 76 = 3x - 5 76 + 5 = 3x 81 = 3x x = x = 27 Therefore, the bases PO = x – 5 = 27 – 5 = 22 cm TS = 2x = 2(27) = 54 cm
  • 19.
    Problem #2b Given: If m T= 2x + 5 ∠ and m S= 3x- ∠ 10, what is m O? ∠ Solution Step 1: Draw the quadrilateral
  • 20.
    The relationship between ∠Tand S in trapezoid POST is that ∠ they are congruent. We need to equate the given expressions to find the value of x, eventually the m T and ∠ m O as they are supplementary. ∠ Step 2: Analyze the Problem
  • 21.
    Step 3: Solvethe Problem 2 + 5 = 3 10 𝑥 𝑥 − 10 + 5 = 3x-2x x = 15 ∠T = 2x + 5 =2(15) + 5 = 30 + 5 ∠T = 35° ∠T + O = 180 ∠ 35 + O = 180 ∠ ∠O = 180 35 − ∠O = ° 𝟏𝟒𝟓 ∠T + O= 180 ∠ 35° + ° = 180° 𝟏𝟒𝟓
  • 22.
    Problem #3a Given: Quadrilateral LIKE is akite a. is twice . If its perimeter is 240 cm, how long is ? Solution Step 1: Draw the quadrilateral
  • 23.
    The perimeter ofthe kite will be used to find the value of x and eventually the length of . P = 2 ( + ) Step 2: Analyze the Problem
  • 24.
    Step 3: Solvethe Problem 240 = 2(x + 2x) 240 = 2(3x) 240 = 6x = x 𝒙 = 40 Therefore, = 2x = 2(40) = 80 cm
  • 25.
    Application a 9 13 23 25 b c d Direction: Choosethe correct answer. 1. CDAB below is a rhombus with m ADB = ⊡ ∠ 6x+ 20 and m BDC = 80 ∠ 0 . What is the value of x?
  • 26.
    Application a b c d Direction: Choose thecorrect answer. 2. Using the figure below, what is m ABC? ∠
  • 27.
    Application a 5 𝑐𝑚 b c d Direction:Choose the correct answer. 3. ABCD below is a parallelogram with = 3x+ ⊡ 5 cm, = 4x – 5 cm, and = 6x – 10 cm. What is length of ? 11𝑐𝑚 15𝑐𝑚 20𝑐𝑚
  • 28.
    Application a 50𝑐𝑚 b c d Direction: Choosethe correct answer. 4. Using the figure below, what is the perimeter of the parallelogram? 6 0𝑐𝑚 70𝑐𝑚 80𝑐𝑚
  • 29.
    Application a 3 b c d Direction: Choosethe correct answer. 5. HYUN below is a square with diagonal = ⊡ 7x – 20 cm and = 3x + 4 cm. Find the value of x 5 6 9