what is the equation of a circle with center (2,-3) and radius 3?
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Answer: The answer is A
Step-by-step explanation:
Equation of a circle: (x-a)^2+(y-b)^2=r^2, where a and b are the coordinates of a center, r - radius
So, you have (2,-3) as a center, and radius r is 3.
Then, your equation is (x-2)^2+(y+3)^2=9
the equation of a circle with center at (h,k) and radius of r is
(x-h)^2+(y-k)^2=r^2
so
(2,-3) and radius is 3
(x-2)^2+(y-(-3))^2=3^2
(x-2)^2+(y+3)^2=9