Question

What is the value of r if the line that passes through ( 4,3 ) and ( -5,r ) has a slope of -1

Answer 1

r= 12

Explanation:

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

Using the formula above,

`(r - 3)/( - 5 - 4) = - 1 \\ (r - 3)/( - 9) = - 1 \\ r - 3 = - 1( - 9) \\ r - 3 = 9 \\ r = 9 + 3 \\ r = 12`