Question

Right in equation of a circle giving it’s center and radius or diameter.

Answer 1

The equation of a circumference can be written as follows:

`(x-a)^2+(y-b)^2=r^2`

Here r is the radius, and the center of the circle is located at point (a, b). Knowing that it is now easy to find the equation. The diameter of the circle is 8, therefore its radius is 4:

r = 4

a = -7

b = -4

Replacing the values:

`(x-(-7))^2+(x-(-4))^2=4^2`

Rearranging the equation, we have finally that the equation of a circle with center in (-7, -4) and diameter 8 is:

`(x+7)^2+(x+4)^2=16`