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If (−4, 11) and (−6, 5) are the endpoints of a diameter of a circle, what is the equation of the circle?

1 Answer

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The equation of the circle is given as:


(x+5)^2 + (y-8)^2 = 10

Solution:

Given that,

(−4, 11) and (−6, 5) are the endpoints of a diameter of a circle

The standard form of the equation of a circle is:


(x-a)^2 + (y-b)^2=r^2

Where,

(a, b) are the co-ordinates of the centre and r is the radius

To find the centre:

Find the midpoint of two given points


m = ((x_1+x_2)/(2) , (y_1+y_2)/(2))


m = ((-4-6)/( 2), (11+5)/(2))\\\\m = (-5, 8)

calculate the radius using the distance formula

Distance between center and one end point = radius

(-5, 8) and (-4, 11)


d = √((x_2-x_1)^2 + (y_2-y_1)^2)


d = √((-4+5)^2 + (11-8)^2)\\\\d = √(1 + 9)\\\\d = √(10)

The equation of the circle is given as:


(x-a)^2 + (y-b)^2=r^2


(x+5)^2 + (y-8)^2 = (√(10))^2\\\\(x+5)^2 + (y-8)^2 = 10

Thus the equation of circle is found

User Andrey Markeev
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