SOLUTION: what is x^2-2x+y^2+4y+1=0 and please graph

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Question 961238: what is x^2-2x+y^2+4y+1=0
and please graph
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-2x%2By%5E2%2B4y%2B1=0...first complete squares
%28x%5E2-2x%2B_%29-_%2B%28y%5E2%2B4y%2B_%29-_%2B1=0
%28x%5E2-2x%2B1%29-1%2B%28y%5E2%2B4y%2B4%29-4%2B1=0
%28x-1%29%5E2-cross%281%29%2B%28y%2B2%29%5E2-4%2Bcross%281%29=0
%28x-1%29%5E2%2B%28y%2B2%29%5E2-4=0
%28x-1%29%5E2%2B%28y%2B2%29%5E2=4
as you can see, you have a circle %28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2, where h=1, k=-2, and r=2; so, the center is at (1,-2)