Question

What is the slope of the line that passes through the points (-6,13) and (9,-7)?

Answer 1

To find the slope of a line that pases through points (x1, y1) and (x2, y2) you use this formula:

`m=\frac{y_2-y_1}{x_2-x_1_{}_{}}`

Where 'm' is the slope. You have to always follow the rule on which number you put first. Pick one of the points and call it (x1,y1) and the other will be (x2,y2). This way you'll always get the right sign for the slope.

In this problem we'll call:

`(x_1,y_1)=(9,-7)`

And

`(x_2,y_2)=(-6,13)`

So, the slope is:

`m=(13-(-7))/((-6)-9)=(13+7)/(-(6+9))=(20)/(-15)=-(4)/(3)`