4x+.5y=20, 2x-2y=10
solve the following problems for the varialbles given
Multiply the first equation by 4.
4 * (4x + .5y) = 20 * 4
16x + 2y = 80
Add the second equation to that.
16x + 2y = 80
+(2x - 2y = 10)
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18x = 90
18x = 90
x = 90 / 18
x = 5
Plug that into equation two.
2x - 2y = 10
2(5) - 2y = 10
10 - 2y = 10
-2y = 10 - 10
-2y = 0
y = 0
Use equation one to verify
4x + .5y = 20
4(5) + .5(0) = 20
20 + 0 = 20
20 = 20
x = 5, y = 0