25x−13y+1=02x+2y=7
25x−13y+1=02x+2y=7
求值:x(x+2y)-(x+1)2+2x,其中x=125,y=−25
等式|x−y|=(x+y)
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1,xy=−12
1、x(x-y)(x+y)-x(x+y)^2
解下列方程组:(1)x−y=13x=6y−7
已知方程组7x+3y=45x−2y=m−1
已知|3x−2y−1|+5x+7y−12=0
解方程组:(1)y=x−13x+2y=8
解方程组:2x−y=3(1)3x+y=7(2)
解方程组:(1)7x+3y=100y=20−2x
1) (2x+5y)(2x-5y)(-4x^2-25y^2) 2) [(x+y)(x-y)-(x-y)^2+2y(x-y