Answer
See graph and explanations.
Work Step by Step
Step 1. Given $\frac{x^2}{25}+\frac{y^2}{16}=1$, we can identify $a^2=25, b^2=16$; thus $c=\sqrt {a^2-b^2}=3$. The ellipse is centered at $(0,0)$ with a horizontal major axis.
Step 2. We can graph the equation as shown in the figure, and the foci can be located at $(\pm3,0)$
