<s>[INST] how does this translate to a circle with radius 5: $\sqrt{24-2x-x^2}$ I tried squaring both sides to get this $y^2 = 24-2x-x^2$, then putting the $x$'s with the $y$'s to get $y^2 + x^2 + 2x = 24$. Then I tried dividing everything by 24, but I don't see it. Tried factoring too.
 [/INST] equation of circle in general form is 
$$  x^2 + y^2 + (2\times g \times x) + (2\times f \times y) + c = 0 $$ 
$$\boxed{Radius =  \sqrt{g^2 + f^2 -c }}$$  
compare this with your equation 
$$   x^2 + y^2 + (2\times 1 \times x) + (2\times 0 \times y) + (-24) = 0 $$ 
here g = 1 , f =0 , c = -24 
so radius = $ \sqrt { 1^2 +0^2 -(-24)} $
= $\sqrt {25 } $
= 5
From above way  the tedious job of factorizing is eliminated .
The equation given in your case is equation in general form
Why I suggested this solution is that sometimes it is tedious to change a equation from general form $  x^2 + y^2 + (2\times g \times x) + (2\times f \times y) + c = 0 $ , to standard form $ (x-a)^2 + (y-b)^2 = (radius)^2 $, in those cases the radius formula given above will be helpful .
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