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Please help me asap!

Please help me asap!-example-1
User Kachilous
by
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1 Answer

4 votes

Answer:

The correct answer option is d. (h, k) = (3, -6), r = 5

Explanation:

We are given the following equation of a circle:


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

and we are to find the center and radius of the circle.

Using the completing the square method:


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

Arranging the like terms together to get:


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

Now completing the square by dividing the coefficient of x and y by 2 and adding their squares to each side of the equation:


(x^2-6x+9)+(y^2+12y+36)=-20+9+36

Rewriting the equation in the form of perfect squares to get:


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

Comparing it to the standard equation of the circle:


(x-h)^2+(y-k)^2=r^2 where the center =
(h, k)

So the coordinates of the center will be (3, -6).

While the radius =
√(25) = 5.

User Eversor
by
7.9k points