Consider the circle such that points A(-3,1) and B(-3,-5) are on the circle and the radius is 7 units. The center of the circle is somewhere in quadrant IV.
A) What are the exact coordinates of the center?

Question

Consider the circle such that points A(-3,1) and B(-3,-5) are on the circle and the radius is 7 units. The center of the circle is somewhere in quadrant IV.
A) What are the exact coordinates of the center?

hero · Answer

Begin with the standard form of a circle: 
$$(x - h)^2 + (y-k)^2 = r^2$$

Input both points separately, creating a system of two equations: 
$$(-3-h)^2 + (1 - k)^2 = 7^2$$
$$(-3 - h)^2 + (-5 - k)^2 = 7^2$$

hero · Answer

Solve for (h,k)