Question

What is the diameter of a circle with the equation (x – 4)2 + (y + 6)2 = 64?

a. 4
b. 8
c. 16
d. 64

Answer 1

C. 16

Explanation:

Edge!

Answer 2

16

Explanation:

step one:

given data

we are given the equation of the circle as

`(x -4)2^ + (y + 6)^2 = 64`----------------1

We know that the general equation for a circle is

`( x - h )^2 + ( y - k )^2 = r^2`--------------2

comparing the two equations above, we can immediately compare the term on the other side of the equality sign that is

r^2=64

square root both sides

r=√64

r=8

since the radius is 8, hence the diameter is

d=2

r= 2*8

=16