Since this is a square, all of the sides are equal to each other.
That means we can take the two sides with an
term in them (the bottom and the right ones) and set up an equation that has them equal to each other and then solve for
:
Let's move the terms with an
to the left side of the equation:
Now we can divide both sides by -2 to get
by itself.
We can plug this into either of those sides to get the length of the sides of the square:
Now that we know each side of the square is of length 6, we can take one of the remaining sides and set it equal to 6 and solve for
: