Question

Enter the equation of the circle with C(5, -13) and radius r = 36.

Answer 1

Answer:

(x+3)²+y²=36

Step-by-step explanation:

The equation of a circle is  

( x − h ) ² + ( y − k ) ² = r ²   , where  ( h , k )  is the center and  r  is the radius.

If the center is at  ( − 3 , 0 )  and the endpoint of the radius is at  ( 3 , 0 )

, then the length of the radius is the distance between the two points, which is  3 − ( − 3 ) = 6 .

We can substitute  

(

−

3

,

0

)

for  

(

h

,

k

)

, and  

6

for  

r

.

(

x

−

h

)

2

+

(

y

−

k

)

2

=

r

2

(

x

−

(

−

3

)

)

2

+

(

y

−

0

)

2

=

6

2

(

x

+

3

)

2

+

y

2

=

36

Answer 2

(x-a)^2 + (y-b)^2=r^2
Where a and b is the center of the circle. Therefore your answer is:
(x-5)^2 + (y+13)^2=1296