Question

Write the equation of the circle with center (−1, −3) and (−7, −5) a point on the circle.

Answer 1

Answer:

Step-by-step explanation:

The standard form of a circle is

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

We have everything we need to fill this in and solve for the radius.

$(-7-(-1))^2+(-5-(-3))^2=r^2$  and

$(-7+1)^2+(-5+3)^2=r^2$  and

$(-6)^2+(-2)^2=r^2$ so

$r^2=40$

Now we can write the equation using the center and the radius we just found:

$(x+1)^2+(y+3)^2=40$