hi
the formula for a circumference is (x-h)²+(y-k)²=radius² with center (h;k)
we need to find h so that (x-h)² gives us x² and 4x
(x-(-2))² = x²+4x+4, so h=-2
so A) is the correct answer, we can still keep going to se if the answer is correct
we now have (x-(-2))²+(y-k)²=gamma-4
so radius = square root (gamma-4)
if k=0 then (y-0)²=y², so answer A) is definitely the solution
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