Question

The points (7,r) and (8,9) fall on a line with a slope of 5. What is the value of r?

Answer 1

Answer:

r = 4

Step-by-step explanation:

Calculate the slope m using the slope formula and equate to 5

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (7, r ) and (x₂, y₂ ) = (8, 9)

m = $\frac{9-r}{8-7}$ = $\frac{9-r}{1}$ = 9 - r = 5 ( subtract 9 from both sides )

- r = - 4 ( multiply both sides by - 1 )

r = 4