Find the standard form of the equation of the specified circle.
Center: (2, -7); point on circle: (-2, -5)
I know that part of the equation is (x-2)^2 + (y- -7)^2=
But I don' know what it equals to. Can anyone help me by writing out the steps to the problem. I would appreciate any help. Thank you in advance :)
Center: (2, -7); point on circle: (-2, -5)
I know that part of the equation is (x-2)^2 + (y- -7)^2=
But I don' know what it equals to. Can anyone help me by writing out the steps to the problem. I would appreciate any help. Thank you in advance :)
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Yup, you got the first part right. All you need to find is r² (radius squared) now.
Standard Form of the equation a circle, as you know, is (x - h)² + (y - k)² = r²
You're provided your center already: (2, -7)
Your equation is now (x - 2)² + (y + 7)² = r²
You're also provided a point, (-2, -5). You can insert this point into your equation, and then solve for r².
(-2 - 2)² + (-5 + 7)² = r²
(-4)² + (2)² = r²
20 = r²
Your equation is now...
(x - 2)² + (y + 7)² = 20
Standard Form of the equation a circle, as you know, is (x - h)² + (y - k)² = r²
You're provided your center already: (2, -7)
Your equation is now (x - 2)² + (y + 7)² = r²
You're also provided a point, (-2, -5). You can insert this point into your equation, and then solve for r².
(-2 - 2)² + (-5 + 7)² = r²
(-4)² + (2)² = r²
20 = r²
Your equation is now...
(x - 2)² + (y + 7)² = 20
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It would seem that the radius of the circle is what you need to find. The formula calls for plugging in the center as x and y and the coordinates of a point (h,k). You have the center co-ordinates properly located in your formula...