Question 1082830
The diameter of a circle has endpoints P (0; 0) and Q(8;-4) : The equation of the circle is
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Use commas, not semi-colons.
endpoints P (0,0) and Q(8,-4)
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the center is the midpoint, call it C.
C is (4,-2).  Do you know how to find that?
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The radius is the distance from C to either P or Q.
r^2 = 4^2 + 2^2 = 20
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The equation of a circle with its center at (h,k) and radius r is
{{{(x-h)^2 + (y-k)^2 = r^2}}}
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Which one matches that, if any?
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