Math
posted by Andrea .
Suppose you have two alcohol+water solutions. One solution ( of volume x liter ) is 45% alcohol, while the second solution (of volume y liter) is 75% alcohol. What values of "x" and "y" (in liters) will fill a total volume of 5.0 liter which contains 2.88 liters of alcohol ?
I need to make two equations from this and use the substitution or elimination method to solve this problem.

x + y = 5.0
0.45 x + 0.75 y = 2.88
Now you do the algebra.