(a+3)(a-3)-(4-a)(a+4)

Question

(a+3)(a-3)-(4-a)(a+4)

Answer 1

A^2 - 9 - (16 - a^2) = a^2 - 9 - 16 + a^2 = 2a^2 - 25 

Answer 2

A²-9-(16-a²)=a²-9-16+a²=2a²-25