(4x-3y)(5x+2y)-2x(9x-5y) 等于多少
问题描述:
(4x-3y)(5x+2y)-2x(9x-5y) 等于多少
答
(4x-3y)(5x+2y)-2x(9x-5y)
=20x^2+8xy-15xy-6y^2-18x^2+10xy
=2x^2+3xy-6y^2