Question

What is an equation in point-slope form of the line that passes through (-7.1) and (-3.9)?

Answer 1

Answer:

$y-1=2(x+7)$

Step-by-step explanation:

Point-slope form: $y-y_1=m(x-x_1)$ where a given point is $(x_1,y_1)$ and the slope is $m$

1) Find the slope of the line (m)

Slope = $\frac{y_2-y_1}{x_2-x_1}$ where the given points are $(x_1,y_1)$ and $(x_2,y_2)$

Plug in the points (-7,1) and (-3,9)

$= \frac{9-1}{-3-(-7)}\\= \frac{8}{-3+7}\\= \frac{8}{4}\\= 2$

Therefore, the slope of the line is 2. Plug 2 into the equation as m:

$y-y_1=2(x-x_1)$

2) Plug one of the given points into the equation

We plan either plug in (-7,1) or (-3,9) and it would work either way. Below you can see the equation plugging in the point (-7,1):

$y-1=2(x-(-7))\\y-1=2(x+7)$

I hope this helps!