Question

Срочноо!!! Помогите 4 и 5

Answer 1

1.4
(x-3)(x+4)=x²
x²+4x-3x-12-x²=0
x-12=0
x=12

1.5
(a^8*(a^2)^-3)/a^7=a^(8-6-7)=a^-5