P E M D A S
Parentheses first:
So, 12 + 4 x 13 - 2
12 + 52 - 2
64 - 2
62
2(4 - 2r) = -2(r + 5)
First, divide both sides by -2. / Your problem should look like:
Second, regroup your terms. / Your problem should look like:
Third, add 4 to both sides. / Your problem should look like:
Fourth, add r + 5 + 4 to get r + 9. / Your problem should look like:
Fifth, subtract r from both sides. / Your problem should look like:
Sixth, subtract 2r - r to get r. / Your problem should look like:

Answer:
r = 9
The answer to your question, is 4 inches
hope this helps :D