Answer
$\text{$y-$intercept: }
-4$
Work Step by Step
Setting $x=0$ and then solving for $y$, then the $y-$intercept of the given equation, $
y=x^2+2x-4
,$ is
\begin{array}{l}\require{cancel}
y=(0)^2+2(0)-4
\\\\
y=0+0-4
\\\\
y=-4
.\end{array}
Hence, the $y-$intercept is
\begin{array}{l}\require{cancel}
\text{$y-$intercept: }
-4
.\end{array}