Question 1022017
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y = 3x + 16,    (1)
x = 2y - 72.    (2)

Substitute the expression y = 3x + 16 of (1) into the equation (2).
You will get a single equation for x:

x = 2*(3x + 16) - 72.


Simplify and solve it.

x = 6x + 32 - 72,

5x = 40,  --->  x = {{{40/5}}} = 8  --->  y = 3x + 16 = 3*8 + 16 = 40.
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