Solve for x and y simultaneously x-3 2y=0 2y^2 3x^2 4xy=9
Don't know what's missing, but since you have a - sign, I'll sssume your + key is malfunctioning. If we go with
x-3+2y=0
then x = 3-2y
Plug that into the other equation and you have
2y^2-3(3-2y)^2-4(3-2y)y=9
or,
2y^2-24y+36 = 0
Then, using the quadratic formula,
y = 6±3√2