Question

Please help and explain 15 points

Write an equation of a circle with the given center and radius center (3,4) and radius 6
A.) (x-3)^2 + (y-4)^2 = 36
B.) (x-3)^2 + (y-4)^2 = 6
C.) (x-3)^2 + (y-4)^2 =36
D.) (x+3)^2 + (y-4)^2 = 6

Answer 1

a

Explanation:

General equation of a circle :
`(x-h)^2+(y-k)^2=r^2`

where (h,k) is at center and r = radius

Here, we want to find the equation of a circle with a given center at (3,4) and a given radius of 6

This is very simple, all we have to do is assign variables and then plug in the values of the variables into the general equation of a circle

First lets assign variables.

(h,k) is center and the circle has a given center at (3,4)

so (h,k) = (3,4) thus, h = 3 and k = 4

r = radius and the circle has a given radius of 6 so r = 6

now we plug this into the general equation of a circle.

recall equation : (x-h)² + (y-k)² = r²

h = 3, k = 4 and r = 6

plug in values

(x-3)² + (y-4)² = 6²

simplify exponent

(x-3)² + (y-4)² = 36

and we are done!

The answer is A