Question: The circle centered at $(−1,−8)$ with radius $9$ can be parametrized in many ways, this still happens even if we impose the extra constraint that the circle must be traversed in the counter-clockwise direction. This problem asks you to work with two of those counter-clockwise parametrizations.
a). If $x = -1 + 9 \cos(t)$
b). If $x = -1 + 9 \sin(t)$
So this is what i have so far, i know that equation of a circle is $x^2+y^2=r^2$
I put the points into the equation $(x+1)^2+(y+8)^2=9^2$
Then I solved for $y$ and plugged in a). as a substitute to get the answer, which I believe is: $y=1-9\cos(t)$
But i get a wrong answer, I am not to sure where to I am messing up, I think I am missing a couple of steps, but i just don't know how to get there.
Hint: Recall for a circle $(x-a)^2 + (y-b)^2 = r^2$, we can convert it into the parameterized equation $$\begin {matrix} x = a + r \cos t \\ y = b + r \sin t \end {matrix}$$ What is the equation given your points $(-1, -8)$ and radius $9$?