因式分解用主元法15x²-20xy-x+8y-2

问题描述:

因式分解用主元法15x²-20xy-x+8y-2

15x²-20xy-x+8y-2=15x²-(20y+1)x+2(4y-1)=[3x-(4y-1)](5x-2)=(3x-4y+1)(5x-2)