Question

Write in slope-intercept form an equation of the line that passes through the points (−1,12) and (1,2).

Answer 1

`y=-5x+7`

Explanation:

step 1

Find the slope

The formula to calculate the slope between two points is equal to

`m=(y2-y1)/(x2-x1)`

we have

the points (−1,12) and (1,2)

substitute

`m=(2-12)/(1+1)`

`m=(-10)/(2)`

`m=-5`

step 2

we know that

The equation of the line in slope intercept form is equl to

`y=mx+b`

where

m is the slope

b is the y-intercept

we have

`m=-5`

`point\ (1,2)`

substitute in the linear equation and solve for b

`2=-5(1)+b`

`b=2+5=7`

therefore

`y=-5x+7`