Question 328098
Are you solving for little r or big R?

I assume that you are trying to find the value of little r.

Multipy (7 - r) and (9 - r) by -1.

Afterward, (7 - r) becomes (r - 7) and (9 - r) becomes (r - 9).

We now have the following fraction:

Cross-multiply.

2(r - 9) = (r - 7)(r - 9)

After doing the math on paper, I found r to be 9.