Question 714562
 2x = y - 4
-3y = x - 5

Make the factor of 1 variable equal to the factor of the same variable in the other equation.

I'll do both of them. First the x.

(2x)/2=(y - 4)/2
-3y - x = -5

x = 0.5y - 2
-3y - x = -5

Put the value of x from the first equation in the second equation.

-3y - (0.5y - 2) = -5
remember -1 * -2 = +2
-3y - 0.5y + 2 = -5
-3.5y + 2 = -5
-3.5y = -7
y = -7/-3.5
y = 2

put y in any of the original equations and you get your value of x

x = 0.5y - 2
so 
2 = 0.5 y -2
4 = 0.5y
8 = y