SOLUTION: My center 8,-1 & my radius is 4. How do I solve for x & y intercepts and graph it?

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Question 568612: My center 8,-1 & my radius is 4. How do I solve for x & y intercepts and graph it?
Answer by AnlytcPhil(1806) About Me  (Show Source):
You can put this solution on YOUR website!
My center (8,-1) & my radius is 4. How do I solve for x & y intercepts and graph it?
The equation of a circle with center (h,k) and radius r is

(x - h)² + (y - k)² = r²

(h,k) = (-8,-1) and r = 4, so the equation is

(x - 8)² + (y - (-1))² = 4²

(x - 8)² + (y + 1)² = 16

The graph is

 

The x-intercepts are when y=0, so we substitute y=0 in

(x - 8)² + (0 + 1)² = 16
       (x - 8)² + 1 = 16
           (x - 8)² = 15

Use the principles of square roots:

              x - 8 = ±sqrt%2815%29

                  x = 8 ± sqrt%2815%29

The x-intercepts are 

    (8-sqrt%2815%29, 0) and (8%2Bsqrt%2815%29, 0)

which are approximately (4.13,0) and (11.87,0)

Edwin