Question

Спростіть вираз:
(b+5)(b-7)-b(b-2)

Answer 1

$(b+5)(b-7)-b(b-2)=b^2-7b+5b-35-b^2+2b=0-35=-35$

Answer 2

Объяснение:

$(b + 5)(b - 7) - b(b - 2) =b^{2}-7b+5b-35-b\left(b-2\right) =b^{2}-2b-35-b\left(b-2\right) =b^{2}-2b-35-\left(b^{2}-2b\right) =b^{2}-2b-35-b^{2}-\left(-2b\right) =b^{2}-2b-35-b^{2}+2b =-2b-35+2b =-35$