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The equation of a circle is x2+y2−12x+6y+20=0.

What is the radius of the circle?

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r =
units

User Cjn
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1 Answer

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To find the radius of the circle, we need to rewrite the equation of the circle in standard form, which is:

(x - h)^2 + (y - k)^2 = r^2

where (h, k) is the center of the circle and r is its radius.

To rewrite the given equation in standard form, we need to complete the square for both x and y terms:

x^2 - 12x + y^2 + 6y + 20 = 0

(x^2 - 12x + 36) + (y^2 + 6y + 9) = -20 + 36 + 9 (adding and subtracting appropriate terms to complete the square)

(x - 6)^2 + (y + 3)^2 = 25

Comparing this equation with the standard form, we see that the center of the circle is (6, -3) and the radius is sqrt(25) = 5.

Therefore, the radius of the circle is 5 units.

HOPE THIS HELPS!

User Lucky Man
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