已知5分之X=3分之Y,则X+Y分之X加X减Y分之Y,减X的平方-Y的平方分之Y的平方的值为

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已知5分之X=3分之Y,则X+Y分之X加X减Y分之Y,减X的平方-Y的平方分之Y的平方的值为
已知5分之X=3分之Y,则X+Y分之X加X减Y分之Y,减X的平方-Y的平方分之Y的平方的值为

已知5分之X=3分之Y,则X+Y分之X加X减Y分之Y,减X的平方-Y的平方分之Y的平方的值为
已知5分之x=3分之y,则x/x+y加上y/x-y减去y的平方/(x+y)(x-y)
x/5=y/3
因此:y=3x/5
x/(x+y)+y/(x-y)-y²/(x+y)(x-y)
=x(x-y)/(x+y)(x-y)+y(x+y)/(x+y)(x-y)-y²/(x+y)(x-y)
=(x²-xy)/(x+y)(x-y)+(y²+xy)/(x+y)(x-y)-y²/(x+y)(x-y)
=(x²-xy+y²+xy-y²)/(x+y)(x-y)
=x²/(x+y)(x-y)
=x²/(x²-y²)
=x²/[x²-(3x/5)²]
=x²/(x²-9x²/25)
=x²/(16x²/25)
=25/16