Chapter 1 - Functions and Their Graphs - Section 1.3 Properties of Functions - 1.3 Assess Your Understanding - Page 74: 5

$x$-intercepts: $3$ and $-3$ $y$-intercept: $-9$

The $x$-intercepts of an equation can be obtained by plugging $y=0$ into the equation, then solving for $x$ in the resulting equation.. Here we'd have: $0=x^2-9$ $9=x^2$ $\pm\sqrt9=\sqrt{x^2}$ $\pm3=x$ Therefore there are two $x$-intercepts: $3$ and $-3$. The $y$-intercepts of an equation can be obtained by plugging $x=0$ into the equation then solving for $y$ in the resulting equation . Here we have: $y=(0)^2-9$ $y=-9$ Therefore the $y$-intercept: $-9$.