已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y已知X+Y分之X-Y等于3,求代数式X+Y分之2(x-y)减X+Y分之3X+Y
问题描述:
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知X+Y分之X-Y等于3,求代数式X+Y分之2(x-y)减X+Y分之3X+Y
答
X+Y分之X-Y等于3
x=-2y
X+Y分之2(x-y)减X+Y分之3X+Y
=(-x-3y)/(x+y)
=1