Math 8: Linear Equations with 2 Variables
Section #8: Writing an Equation given 2 Points 8.F.4
Corresponds with Module 4, Lessons 16
Notes #54
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Key Concept!
To Write Linear Equations in Slope Intercept Form given a Two Points.
1) When writing linear equation, write them in the slope intercept form_____________________.
2) To write an equation in slope-intercept form you must:
a. Find the slope: _____________________
b. Find the y-intercept, substitute the _____________ and either point into y = mx + b and
solve for _____.
3) Once you know the slope & intercept, substitute the slope in for ____ and the y-intercept for ___.
Example 1: Write the equation of a line, given the coordinates of two points on the line.
a) Write the equation of the line that passes through the points (5, 4) & (6, 7).
b) Write the equation of the line that passes through the points (4, 2) & (2, 7).
Practice: Write the equation of a line, given the coordinates of two points on the line.
a) (-5, 6), (-2, 12)
a) (4, -2), (6, 1)
You Try: Write the equation of a line, given the coordinates of two points on the line.
1) (-3, 4), (0, -5)
2) (8, 4), (12, 2)
3) (6, -3), (-2, -3)
4) (3, 5), (0, 0)
Math 8: Linear Equations with 2 Variables
Section #8: Writing an Equation given 2 Points 8.F.4
Corresponds with Module 4, Lessons 16
HW #54
_________________________
Write the equation of a line, given the coordinates of two points on the line.
1) (4, 7), (1, -2)
2) (3, 4), (5, -4)
3) (3, -6), (-1, 2)
4) (4, -4), (8, -10)
MORE ON BACK!!
5) For a science experiment, mala measured the height of a plant every week and recorded it in the
following table. Assuming the growth is linear, write an equation to represent the height y of the plant
after x weeks.
Weeks Height
(in.)
5
13
10
14
6)
H.O.T. Problems (Higher Order Thinking). You must try to get homework credit!!!!
After 2 seconds on a penalty kick in soccer, the ball travels 160 feet. After 3 seconds on the same kick,
the ball travels 220 feet. Write an equation to represent the distance y of the ball after x seconds.