(5x+7)(2x-3)-(10x+1)(x-2)怎么做?

问题描述:

(5x+7)(2x-3)-(10x+1)(x-2)怎么做?

(5x+7)(2x-3)-(10x+1)(x-2)
=10x²-x-21-(10x²-19x-2)
=10x²-x-21-10x²+19x+2
=18x-19