Answer:
3.
Step-by-step explanation:
3m^2-3n^2= 3(m^2-n^2) = 3 (m+n)(m-n)
6m-6n= 6 (m-n)
3(m+n)~(m-n)~/6~(m-n)~ = (m+n)/2
Perimeter is 30 and area is 32
7+8+7+8= 30 and A= BH so 8 x 4 = 32