Question

what should be taken away from 2 a - 8 b + 3 a b+ 10 to get -3 a - 7 b - 5 ab + 25

Answer 1

let the required no. be y.

hence,(2a-8b+3ab+10)-y=-3a-7b-5ab+25

hence,y=(2a-8b+3ab+10)-(-3a-7b-5ab+25)

=2a-8b+3ab+10-3a+7b+5ab-25

=-a-b+8ab-15

=8ab-a-b-15