Answer
x-intercepts: $-3$ and $3$
y-intercept: $9$
Work Step by Step
RECALL:
(1) A point where the graph touches or crosses the x-axis is called an x-intercept. Given an equation, the x-intercept/s can be found by setting $y=0$ then solving for $x$.
(2) A point where the graph touches or crosses the y-axis is called a y-intercept.
Given an equation, the y-intercept/s can be found by setting $x=0$ then solving for $y$.
Solve for the x-intercept/s by setting $y=0$ then solving for $x$:
$\begin{array}{ccc}
&y &= &9-x^2
\\&0 &= &9-x^2
\\&0+x^2 &= &9-x^2+x^2
\\&x^2 &= &9
\\&x &= &\pm sqrt9
\\&x &= &\pm \sqrt{3^2}
\\&x &= &\pm3
\end{array}$
The x-intercepts are $\pm 3$.
Solve for the y-intercept/s by setting $x=0$ then solving for $y$:
$\begin{array}{ccc}
&y &= &9-x^2
\\&y &= &9-0^2
\\&y &= &9
\end{array}$
The y-intercept is $9$.