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The endpoints of the longest chord on a circle are (4, 5.5) and (4, 10.5).

The center of the circle is at the point ? and its radius is units ? The equation of this circle in standard form is ?

User Deaponn
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2 Answers

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Answer and Step-by-step explanation:

The longest chord on the circle is the diameter, and the center of the circle is the midpoint of the diameter.

Use the midpoint formula to find the center

the x-coordinates are the same, so you can just subtract the y-coordinates to find the radius.

10.5 - 8 = 2.5

The equation of the circle is (x - h)² + (y - k)² = r² where r is the radius and (h, k) is the center.

(x - 4)² + (y - 8)² = 6.25

User Potashin
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The longest chord on the circle is the diameter, and the center of the circle is the midpoint of the diameter.

Use the midpoint formula to find the center

((x_1+x_2)/(2),(y_1+y_2)/(2))=((4+4)/(2),(5.5+10.5)/(2))=(4,8)

the x-coordinates are the same, so you can just subtract the y-coordinates to find the radius.
10.5 - 8 = 2.5

The equation of the circle is (x - h)² + (y - k)² = r² where r is the radius and (h, k) is the center.

(x - 4)² + (y - 8)² = 6.25
User VoimiX
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