Jane C. answered • 03/07/16
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Using17=x+3y, solve for x.
x = -3y + 17
Substitute x = -3y + 17 into the equation 8=4x-3y
8=4(-3y + 17) -3y
8 = -12y + 68 - 3y
8 = -15y + 68
0 = -15y + 68 - 8
0 = -15y + 60
15y = 60
y = 60/15
y = 4
Solve for x:
8 = 4x - 3y
8 = 4x - 3 (4)
8 = 4x - 12
8 + 12 = 4x
20 = 4x
20/4 = 4x/4
so x = 5
