#### Answer

$y=-\dfrac{1}{12}$

#### Work Step by Step

Adding $
\dfrac{2}{3}
$ to both sides of the given equation, $
-\dfrac{2}{3}+y=-\dfrac{3}{4}
$, then,
\begin{array}{l}
-\dfrac{2}{3}+y+\dfrac{2}{3}=-\dfrac{3}{4}+\dfrac{2}{3}
\\\\
y=-\dfrac{3}{4}+\dfrac{2}{3}
\\\\
y=-\dfrac{9}{12}+\dfrac{8}{12}
\\\\
y=-\dfrac{1}{12}
.\end{array}