write and equation that Passes through (-2, 2) and (2, -12)

Question

 write and equation that Passes through (−2, 2) and (2, −12) 

Answer 1

Hi Joe, given two points, you can find the equation of the line passing through those points by:

 

First, find the slope of the line.

 

Second, use the point-slope method to find the line.

 

Slope:

 

Slope = (-12 - 2) / ( 2 - (-2))

 

Slope = -14 / 4

 

Slope = -7 / 2

 

Point-slope method:

 

y - y₁ = m * (x - x₁)

 

Substitute:

 

y₁ = 2

 

x₁ = -2

 

m = -7 / 2

 

y - 2 = -7 / 2 * (x - (-2))

 

y - 2 = -7 / 2 * x - 7

 

Add 2 to both sides to put the line in slope-intercept form:

 

y = -7 / 2 * x - 5

 

Check:

 

Substitute for x and y using both points:

 

(-2, 2)

 

2 = -7 / 2 * -2 - 5

 

2 = 7 - 5

 

2 = 2, point checks

 

(2, -12)

 

-12 = -7 / 2 * 2 - 5

 

-12 = -7 - 5

 

-12 = -12, point checks

 

Questions?