Answer
$|A|=3$, $p=\pi $, $\phi=\frac{\pi}{4}$.
See graph.
Work Step by Step
Step 1. Given $y=-3sin(-2 x+\frac{\pi}{2})=-3sin[-2(x-\frac{\pi}{4})]$, we can find the amplitude $|A|=3$, period $p=\frac{2\pi}{2}=\pi $, and phase shift $\phi=\frac{\pi}{4}$.
Step 2. See graph.
