(2x-10)(x-10)·5=500怎么算?

问题描述:

(2x-10)(x-10)·5=500怎么算?
写仔细点,谢谢

(2X-10)(x-10)*5=500(2X-10)(x-10)=100(X-5)(x-10)=50X2-15X+50=50X2-15X=0X(X-15)=0X=0 或X=15