Answer
$$\left(\frac{x}{2}\right)^{2}+\left(\frac{y}{4}\right)^{2}+\left(\frac{z}{6}\right)^{2}=1.$$
Work Step by Step
By observing Figure 15(A), we get that
$$ a=2, \quad b=4, \quad c=6.$$
Using the equation of the ellipsoid (page 691) and the above variables, we get:
$$\left(\frac{x}{2}\right)^{2}+\left(\frac{y}{4}\right)^{2}+\left(\frac{z}{6}\right)^{2}=1.$$
