Answer:
Step-by-step explanation:
A graphing calculator can help you see the center is (4, 3) and the diameter is 10, so the radius is 5.
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Or, you can rearrange the equation to standard form by completing the squares.
x² -8x + y² -6y = 0 . . . . . subtract 6y, group terms
(x² -8x +16) +(y² -6y +9) = 16 +9 . . . . . complete the squares by adding the squares of half the coefficient of the linear term: (-8/2)²=16, (-6/2)²=9.
(x -4)² + (y -3)² = 25 . . . . . rewrite in standard form
Compare this to ...
(x -h)² + (y -k)² = r²
and recognize the center (h, k) is (4, 3), and the radius is √25 = 5.
