Question

1) (2а+1)(2а-1)+(а-7)(а+7)
2) (х-3)(х+3)-(х+8)(х-8)

Answer 1

1)=4a^2-1+a^2-49=5a^2-50=5(a^2-10)
2)=x^2-9-x^2+64=2x^2+55=2(x^2+22,5)