已知2X+3Y=0,求(5X+4Y)/(3X-2Y)的值

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已知2X+3Y=0,求(5X+4Y)/(3X-2Y)的值

已知2X+3Y=0,求(5X+4Y)/(3X-2Y)的值
已知2X+3Y=0,求(5X+4Y)/(3X-2Y)的值

已知2X+3Y=0,求(5X+4Y)/(3X-2Y)的值
2X+3Y=0
2X=-3Y
X=-1.5Y
(5X+4Y)/(3X-2Y)
=[5*(-1.5Y)+4Y]/[3*(-1.5Y)-2Y]
=(-7.5Y+4Y)/(-4.5Y-2Y)
=(-3.5Y)/(-6.5Y)
=35/65
=7/13

2x+3y=0则x/y=-3/2,设x=3k,y=-2k
则5x+4y=7k,3x-2y=13k
(5X+4Y)/(3X-2Y)=7/13

因为2X+3Y=0,所以X=-1.5Y
代入(5X+4Y)/(3X-2Y)得到
(4-7.5)Y/(-4.5-2)Y
=3.5/6.5
=7/13
祝你开心~

由2X+3Y=0 可得X/Y=-1.5
(5X+4Y)/(3X-2Y)上下同除Y,可得(5X/Y+4)/(3X/Y-2)=(-7.5+4)/(-4.5-2)=7/13

2X+3Y=0
X=-3Y/2
(5X+4Y)/(3X-2Y)=(-15Y/2+4Y)/(-9Y/2-2Y)=(-7/2)/(-13/2)=7/13