SOLUTION: The lines y = 4x/3 - 5/3 and y = -4x/3 - 13/3 each contain diametres of a circle and the point (-5,0) is also on that circle. Find the equation of the circle

1.  Find the intersection point of these lines.
    It is the center of the circle.

    To find it, solve the system.


    The center is (x,y) = (-1,-3).


2. The distance from the center to the point (-5,0) is  = 5.


3.  The equation of the circle is 

     = 25.