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considering the 2 equations below which expression can be substituted for y in the bottom equation of the system to solve the system by substitution



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Gene G. | You can do it! I'll show you how.You can do it! I'll show you how.
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To solve a system of equations by substitution, solve one of the equations for one of the variables, then plug that result into the other equation.

We want to solve equation 2 for y, so we need to eliminate the x from that equation.

Solve equation 1 for x in terms of y:
y-3x = 4
-3x = -y + 4
x = y/3 - 4/3

Replace the x in equation 2:

3y + 2x = 1
3y + 2(y/3 - 4/3) = 1
Now the equation only has the variable y and you can solve it.

The answer to the original question is:
y/3 - 4/3