Acircle is centered at (5, 4) and has radius 6. write its equation in standard form.
a) (x - 5)2 + (y - 4)2 = 6
b) (x + 5)2 + (y + 4)2 = 6
c) (x - 5)2 + (y - 4)2 = 36
d) (x + 5)2 + (y + 4)2 = 36

A circle equation is (x – h)^2 + (y – k)^2 = r^2 where (h,k) is the center and r is the radius. Now all we have to do is plug in the variables. 

Since (h,k)=(5,4) and r= 6

The answer would be C. 

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