Question

Find the area enclosed by the ellipse $\frac{x^2}{25}+\frac{y^2}{16}=1$
(Draw the figure in answer-book)

Answer 1

Area enclosed by an ellipse $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1$ is given by $\pi ab$

Here, for the ellipse $\frac{x^2}{25}+\frac{y^2}{16}=1,a=5$ and $b=4$

The area thus becomes $\pi \times 5\times 4=20\pi$