Question

The slope goes through (2,5) and (7,r) and equals 1/3 what is r

Answer 1

The fromula of a slope:

`m=(y_2-y_1)/(x_2-x_1)`

We have

`(2,\ 5);\ (7,\ r),\ m=(1)/(3)`

Substitute:

`(r-5)/(7-2)=(1)/(3)\\\\(r-5)/(5)=(1)/(3)\qquad|\text{cross multiply}\\\\3(r-5)=(5)(1)\qquad|\text{use distributive property}\\\\3r-15=5\qquad|\text{add 15 to both sides}\\\\3r=20\qquad|\text{divide both sides by 3}\\\\r=(20)/(3)`