Question

几道提公因式法计算题,1.4乘(x-y)的平方减去x乘（y-x).(这都题写的时候能不能说一下每个步骤为什么这样写,或者

Answer 1

1.

4乘(x-y)的平方减去x乘（y-x)

=4(x-y)^2-x(y-x)

=4(x-y)^2+x(x-y)

=(x-y)(4x-4y+x)

=(x-y)(5x-4y)

2.

(55x+35)(53x+26)-(55x+35)(53x+27)=0

(55x+35)(53x+26-53x-27)=0,

-(55x-35)=0,

11x-7=0,

x=7/11