Question

Write the equation of the circle with center (0,0) and (-1,-3)

Answer 1

x^2 + y^2 = 10.

Explanation:

The square of the radius is (-1)^2 + (-3)^2 = 1 + 9

= 10.

The general form is x^2 + y^2 = r^2

so here it is x^2 + y^2 = 10.