SOLUTION: I am confused as to how to find the radius and center of a circle by using an equation. Here's the equation: x^-4x+y^+2y=-1

Algebra ->  Circles -> SOLUTION: I am confused as to how to find the radius and center of a circle by using an equation. Here's the equation: x^-4x+y^+2y=-1      Log On


   

Question 84318This question is from textbook
: I am confused as to how to find the radius and center of a circle by using an equation. Here's the equation:

x^-4x+y^+2y=-1 This question is from textbook

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
You must complete the square on the x and y terms respectively:
x%5E2-4x+%2By%5E2%2B2y=-1

You must "complete the square" by taking HALF of the x coefficient, and SQUARE the result, adding this amount to each side of the equation. Repeat by taking HALF of the Y coefficient, SQUARE, and add to each side of the equation. It should look like this:
x%5E2-4x%2B____%2By%5E2%2B2y%2B____=-1%2B____%2B____
x%5E2-4x+%2B+4++%2By%5E2%2B2y%2B1=-1%2B4%2B1
+%28x-2%29%5E2+%2B%28y%2B1%29%5E2+=+4

The center is at x=2 and y=-1, and r^2 = 4.
Therefore, the center is (2,-1) and r=2.

R^2 at SCC