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Which equation represents a circle that contains the point (-5, 3) and has a center at (-2, 1)? Distance formula: vaa -02 (x - 1)2 + ( + 2)2 = 25 (x + 2)2 + (-1)=5 O (* + 2) + (-1) - 25 (x-1) + ( + 2) = 5



User Esraa Abdelmaksoud
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1 Answer

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11 votes

Given:

The center of the circle = (-2,1).

Circle passes through the point (-5,3).

To find:

The equation of the circle.

Solution:

Radius is the distance between the center of the circle and any point on the circle. So, radius of the circle is the distance between the points (-2,1) and (-5,3).


Distance=√((x_2-x_1)^2+(y_2-y_1)^2)


r=√((-5-(-2))^2+(3-1)^2)


r=√((-5+2)^2+(2)^2)


r=√((-3)^2+(2)^2)

On further simplification, we get


r=√(9+4)


r=√(13)

The standard form of a circle is:


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

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

Substitute h=-2, k=1 and
r=√(13).


(x-(-2))^2+(y-1)^2=(√(13))^2


(x+2)^2+(y-1)^2=13

Therefore, the equation of the circle is
(x+2)^2+(y-1)^2=13.

User Yvanna
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