Question 193436
This graph is a circle, but a function has only one y-value
for each x. The circle has 2 y-values for most of the x's,
so the circle has to be split up into 2 half-circles, and
each half-circle is a function.
{{{x^2=36-y^2}}}
{{{y^2 = 36 - x^2}}}
{{{y = sqrt(36 - x^2)}}}
and
{{{y = -sqrt(36 - x^2)}}}
I'll plot both of these on the same graph
{{{ graph( 400, 400, -7, 7, -7, 7, sqrt(36 - x^2), -sqrt(36 - x^2)) }}}