C= 2 x r where r = 8
C = 2 x 8
C = 16.
Hope I helped:)
When doing this equation, draw a big X on your paper. At the top of the x you do A times C. At the bottom, you put the B. To factor, you need to find what two numbers MULTIPLY together to equal the A times C, and that add together to get the B.
In all you will get (q+7) (q-6)
