## Calculus 8th Edition

Given: $x^{2}+4y^{2}=16$ Divide both sides by $16$ $\frac{x^{2}}{16}+\frac{y^{2}}{16}=1$ $\frac{x^{2}}{4^{2}}+\frac{y^{2}}{2^{2}}=1$ which is the standard form of the equation of an ellipse.