Answer
$x = 4$
Work Step by Step
The coefficients of the $y$ term differ only in sign, so if we add these equations without modification, we will cancel out the $y$ term and can then solve for $x$:
Let us add the equations. First, we cancel out the $y$ term:
$x + y = -3$
$x - y = 11$
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$x = -3$
$x = 11$
Now we add both sides of the two equations to get:
$$2x = 8$$
Divide by $2$ to solve for $x$:
$$x = 4$$
