Question

2x(x+1)-5x(x-1) упростить

Answer 1

$2x^2+2x-5x^2+5x=-3x^2+7x$

Answer 2

$2x(x+1)-5x(x-1)=2x^2+2x-5x^2+5x=\\ =(2-5)x^2+(2+5)x=-3x^2+7x$