# How do you graph #y=2sqrt(9-x^2)#?

##### 1 Answer

Jun 8, 2015

This is the upper half of an ellipse with endpoints on the

To see this, first square both sides of the equation to get:

Then add

This is in the general form of the equation of an ellipse:

However, the square root sign denotes the positive square root, so the original equation only represents the upper half of the ellipse.

graph{2sqrt(9-x^2) [-10.085, 9.915, -2, 8]}