Question

(7x-8)(7x+8)-7x(7x+8) при x=3,5

Answer 1

(7x-8)(7x+8)-7x(7x+8)= 49x^2  - 64   -49x^2  -56x =  - 64 -56x= -64 -56*3.5=
= -64 -196= -260.