X/Y=4/3,
X=4Y/3,
(3X^2-5XY+2Y^2)/(2X^2+3XY-5Y^2)
=(X-Y)(3X-2Y)/[(X-Y)(2X+5Y)]
=(3X-2Y)/(2X+5Y)
=[3*(4Y/3)-2Y]/[2*(4Y/3)+5Y]
=2Y/(23Y/3)
=6/23.