(b-8)в квадрате - (64-6b)

(b-8)²-(64-6b)=b²-16b+64-64+6b=b²-10b=b(b-10)

(b-8)^2-64+6b= =b^2-16b+64-64+6b= =b^2-10b=b(b-10)