21
Today:
1. - -3(8)
-2 + -(4)
3. Find the length & width:
2x + 10
x P = 68
2. Solve for x: rx + 9 = h
5
x = 5h -9
r
4. Solve: 2y + 2 < 11+ 3 < 8 + y
Interpreting Linear Functions
and Finding Intercepts
elevation = 12
kilometers
Draw a graph!
Draw a graph!
12 hours
• Linear Equations form straight lines. How do we
determine if an equation is linear?
It can be rewritten in the form: Ax + By = C
This is the Standard Form of a linear equation where:
a.) A and B are not both zero.
b.) The largest exponent is not greater than 1
Determine Whether the Equations are Linear:
1. 4 - 2y = 6x 2. -4/5x = -2 3. -6y + x = 5y - 2
Remember:
This is to determine whether an equation is linear
(forms a straight line) or not. The standard form is also
used to determine x and y intercepts.
Practice Questions:
1. From the table, determine the function, fill in the missing
values, and write the equation solving for y. f(x) =
Find the missing coordinate of a line with points (–2, R) and
(4, 6) and a slope of 3
2
Practice Questions:
If (a,2) is a point on the graph of 2x - 7y = 20, what is a?
R = -3
When to use the point-slope form of a line:
a. If all you have to work with is one point
on the line and the slope of the line
b. If all you have are two points on the line
Write the equation of a line passing through
the point (2,5) with a slope of -2
Practice Questions:
Write the standard form for the equation of the line
through the point (-2, 5) with a slope of 3.
Use the point-slope form, y – y1 = m(x – x1), with m = 3 and
(x1, y1) = (-2, 5). y – y1 = m(x – x1) Point-slope form
y – y1 = 3(x – x1) Let m = 3.
y – 5 = 3(x – (-2)) Let (x1, y1) = (-2, 5).
y – 5 = 3(x + 2) Simplify.
y = 3x + 11 Slope-intercept form
3x – y = - 11 Standard Form
Practice Questions:
Example: Write the equation of the line through the
points (4, 3) and (-2, 5).
y – y1 = m(x – x1) Point-slope form
Slope-intercept formy = - x + 13
3
1
3
2 15 – 3
-2 – 4
= -
6
= -
3
Calculate the slope.m =
Use m = - and the point (4, 3).y – 3 = - (x – 4)
1
3 3
1
Find the x-intercept of the line with slope of 2 and
passing through the points (-1, 2) and (0,4)
Find the equation of the line that has a slope of 𝟑 and a y-intercept of
-1. Graph the line and write the equation in both slope-intercept and
standard forms with integers only for the standard form.
The only information you have is the slope
𝟑
𝟒
, and a point on the
line, (1,2). Use the correct equation & graph the line. Then write
the equation in standard form with integers only.
You begin with the point-slope formula,
which becomes the slope-intercept form.
Use the slope-intercept to graph.
To put the equation in
standard form, you
can do this...
What if:
Practice Problems
Practice Problems
Standard Form,
No fractions
1. A line with the equation: y = 2x -5 will never touch
what quadrant of the coordinate plane?
2. A line with the equation: -3x – y = 6 will never touch
what quadrant of the coordinate plane?
Practice Problems
x
y
What is the equation of the line shown?
Practice Problems
y =
𝟏
𝟐
x + 2
1. Is the graph a function?
Why or why not?
2. Is the graph a linear function?
Why or why not?
3. What is the per
week rate of change
between weeks 1-3?
4. What is the per
week rate of change
between weeks 6-10?
Practice Problems
Class Work 2.12;
Show All Work
Practice Problems:

January 21, 2015

  • 1.
  • 2.
    1. - -3(8) -2+ -(4) 3. Find the length & width: 2x + 10 x P = 68 2. Solve for x: rx + 9 = h 5 x = 5h -9 r 4. Solve: 2y + 2 < 11+ 3 < 8 + y
  • 3.
  • 4.
  • 5.
    Draw a graph! Drawa graph! 12 hours
  • 6.
    • Linear Equationsform straight lines. How do we determine if an equation is linear? It can be rewritten in the form: Ax + By = C This is the Standard Form of a linear equation where: a.) A and B are not both zero. b.) The largest exponent is not greater than 1 Determine Whether the Equations are Linear: 1. 4 - 2y = 6x 2. -4/5x = -2 3. -6y + x = 5y - 2 Remember: This is to determine whether an equation is linear (forms a straight line) or not. The standard form is also used to determine x and y intercepts.
  • 7.
    Practice Questions: 1. Fromthe table, determine the function, fill in the missing values, and write the equation solving for y. f(x) =
  • 8.
    Find the missingcoordinate of a line with points (–2, R) and (4, 6) and a slope of 3 2 Practice Questions: If (a,2) is a point on the graph of 2x - 7y = 20, what is a? R = -3 When to use the point-slope form of a line: a. If all you have to work with is one point on the line and the slope of the line b. If all you have are two points on the line Write the equation of a line passing through the point (2,5) with a slope of -2
  • 9.
    Practice Questions: Write thestandard form for the equation of the line through the point (-2, 5) with a slope of 3. Use the point-slope form, y – y1 = m(x – x1), with m = 3 and (x1, y1) = (-2, 5). y – y1 = m(x – x1) Point-slope form y – y1 = 3(x – x1) Let m = 3. y – 5 = 3(x – (-2)) Let (x1, y1) = (-2, 5). y – 5 = 3(x + 2) Simplify. y = 3x + 11 Slope-intercept form 3x – y = - 11 Standard Form
  • 10.
    Practice Questions: Example: Writethe equation of the line through the points (4, 3) and (-2, 5). y – y1 = m(x – x1) Point-slope form Slope-intercept formy = - x + 13 3 1 3 2 15 – 3 -2 – 4 = - 6 = - 3 Calculate the slope.m = Use m = - and the point (4, 3).y – 3 = - (x – 4) 1 3 3 1 Find the x-intercept of the line with slope of 2 and passing through the points (-1, 2) and (0,4)
  • 11.
    Find the equationof the line that has a slope of 𝟑 and a y-intercept of -1. Graph the line and write the equation in both slope-intercept and standard forms with integers only for the standard form. The only information you have is the slope 𝟑 𝟒 , and a point on the line, (1,2). Use the correct equation & graph the line. Then write the equation in standard form with integers only. You begin with the point-slope formula, which becomes the slope-intercept form. Use the slope-intercept to graph. To put the equation in standard form, you can do this... What if:
  • 12.
  • 13.
  • 14.
    1. A linewith the equation: y = 2x -5 will never touch what quadrant of the coordinate plane? 2. A line with the equation: -3x – y = 6 will never touch what quadrant of the coordinate plane? Practice Problems
  • 15.
    x y What is theequation of the line shown? Practice Problems y = 𝟏 𝟐 x + 2
  • 16.
    1. Is thegraph a function? Why or why not? 2. Is the graph a linear function? Why or why not? 3. What is the per week rate of change between weeks 1-3? 4. What is the per week rate of change between weeks 6-10? Practice Problems
  • 17.
  • 18.