来自董少龙的问题
【计算题哈,若代数式x^2+y^2-14x+2y+50的值为0.化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]请把每一步写清楚了,】
计算题哈,
若代数式x^2+y^2-14x+2y+50的值为0.
化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]
请把每一步写清楚了,
1回答
2020-07-15 14:46