Question

Write the equation of the circle with center (-2, -5) and containing the point (-10, -20).

Answer 1

Equation for a circle
r^2 = (x - h)^2 + (y - k)^2

where r = sqrt[ (-2 - (-10))^2 + (-5 - (-20))^2]

sqrt[ (8)^2 + (15)^2 ]
sqrt[ 64 + 225 ]
= sqrt[289] = 17

equation for a circle
17^2 = (x - (-2))^2 + (y - (-5))^2


17^2 = (x + 2)^2 + (y + 5)^2