SOLUTION: What is the equation of a circle with a center at (-2, 4) and a radius of 4? A. (x-2)^2 + (y+4)^2 = 16 B. (x+2)^2 + (y-4)^2 = 16 C. (x+2)^2 - (y-4)^2 = 16 D. (x-2)^2 - (y+4)^

Algebra ->  Circles -> SOLUTION: What is the equation of a circle with a center at (-2, 4) and a radius of 4? A. (x-2)^2 + (y+4)^2 = 16 B. (x+2)^2 + (y-4)^2 = 16 C. (x+2)^2 - (y-4)^2 = 16 D. (x-2)^2 - (y+4)^      Log On


   

Question 965562: What is the equation of a circle with a center at (-2, 4) and a radius of 4?
A. (x-2)^2 + (y+4)^2 = 16
B. (x+2)^2 + (y-4)^2 = 16
C. (x+2)^2 - (y-4)^2 = 16
D. (x-2)^2 - (y+4)^2 = 16
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

What is the equation of a circle with a center at (-2, 4) and a radius of 4?
recall the formula: %28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2 where h and k are x and y coordinates of the center, and r is a radius
A.
%28x-2%29%5E2+%2B+%28y%2B4%29%5E2+=+16...here we see that h=2,k=-4 (a center at (2,+-4)), and r=4
B.
%28x%2B2%29%5E2+%2B+%28y-4%29%5E2+=+16...here we see that h=-2,k=4 (a center at (-2,+4)), and r=4
C.
%28x%2B2%29%5E2+-+%28y-4%29%5E2+=+16...here we see that h=-2,k=4,but this is a hyperbola, not a circle
D.
%28x-2%29%5E2+-+%28y%2B4%29%5E2+=+16........this is a hyperbola, not a circle

so, the equation of a circle with a center at (-2,+4) and a radius of 4 is %28x%2B2%29%5E2+%2B+%28y-4%29%5E2+=+16
and your answer is B.