Answer
$x=cos(t), y=4sin(t)$ with $-\frac{\pi}{2}\le t\le\frac{\pi}{2}$.
Work Step by Step
Answer may vary.
1. The half ellipse follows the equation $\frac{x^2}{1}+\frac{y^2}{16}=1$ with $x\ge0$
2. We can write $x=cos(t), y=4sin(t)$ with $-\frac{\pi}{2}\le t\le\frac{\pi}{2}$.
