SOLUTION: (2,-4);x^2+y^2-6x+8y=-15

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Question 831032: (2,-4);x^2+y^2-6x+8y=-15
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
given:
point (2,-4)
x%5E2%2By%5E2-6x%2B8y=-15 ..........first let see what we have here,
complete square
%28x%5E2-6x%2B_%29%2B%28y%5E2%2B8y%2B_%29=-15
%28x%5E2-6x%2B3%5E2%29-3%5E2%2B%28y%5E2%2B8y%2B2%5E2%29-4%5E2=-15
%28x-3%29%5E2-9%2B%28y%2B4%29%5E2-16=-15
%28x-3%29%5E2%2B%28y%2B4%29%5E2=-15%2B9%2B16
+%28x-3%29%5E2%2B%28y%2B4%29%5E2=10.........so, we have a circle with a center coordinates h=3 and k=-4
so, the center is at point (3,-4)
since you are given a point (2,-4), means that given point is not a center