Question

Please help me. I would appreciate it

Answer 1

Let A be the 1st point and B the 2nd:

A(r,-2) and B(7,r) = A(x₁ , y₁) and B(x₂ , y₂)

We know that the slope m =(y₂ - y₁) / (x₂ - x₁)

m= [r - (-2)] / (7 - r) ; m =(r+2)/(7-r) = 8,
Solve for r and you will find r= 6

Answer 2

If you plug in the r values, the only one that will work will be r = 6. (6,-2) & (7,6) put into the slope formula yields: [6-(-2)]/[7-6] = 8/1 = 8 the you needed.