Where are the choices to the problem??
X + y = 16 (1)
x/y = 3 (2)
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x + y = 16
x = 16 - y
1. Substitute x into equation 2
16-y/y = 3
16 - y = 3y
16 = 4y
y = 4
2. Now substitute y into equation 1
x/y = 3
x/4 = 2
x = 12
Therefore, x = 12, y = 4
7x+2=5(x-2)
7x+2=5x-10
7x-5x=-10-2
2x=-12
x=-6
Regards M.Y.