x+y=90 5/8x+5=3/5y x,y分别是多少?
5X +7y=145 5x+3y=105 X是多少.Y是多少
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
x-5y=13且3x+y=20,x.y分别等于多少?
若y:x:z=5:3:8,且7x+3y-5z=8,则x.y.z分别是多少?
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
3x-2y=9 x-3y=2 x+y=5 x+2y=3 y=x 2x+y=8
已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值
(3x-4y)(5x-4y)-(7x-8y)(6y-5x)
(5x+3y)(3y-5x)-(4x-y)(4y+x)=
5(x-y)^2-(x-y)-8(x-y)^2-3(x-y)
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5