## College Algebra (6th Edition)

Vertices: $(2,\ 0)$ and $(-2,0)$. Foci: $(\sqrt{5}, 0)$ and $(-\sqrt{5}, 0)$. Matches graph (b).
The transverse axis lies on the x-axis. $a^{2}=4$ $\mathrm{a}=2$ The vertices are $a$ units from the center $(2,\ 0)$ and $(-2,0)$. The foci are $c$ units from the center. $b^{2}=1$ $c^{2}=a^{2}+b^{2}=4+1=5$ $c=\sqrt{5}$ Foci: $(\sqrt{5}, 0)$ and $(-\sqrt{5}, 0)$. Matches graph (b).