The points (-3,2) and (-2,3) lie on a circle whose center is on the x-axis. What is the radius of the circle?
Pls explain.
Lot the radius be located at (a, 0)
Since the distance from the center to each of these points is the same, we can use the equaion of a circle to find a
(-3 - a)^2 + ( 0 - 2^2 = r^2
(-2 - a) + ( 0 - 3)^2 = r^2
Since r^2 = r^2.....then
(-3 - a)^2 + (0 -2)^2 = (-2-a)^2 + (0 - 3)^2 simplify
a^2 + 6a + 9 + 4 = a^2 + 4a + 4 + 9 subtract like terms from each side
6a = 4a
6a - 4a = 0
a(6-4) = 0
2a = 0
a = 0
So...the center is (0,0)
And the radius is
sqrt [ (-2 - 0)^2 + (0 - 3)^2 ] = sqrt [ 2^2 + 3^2] = sqrt (13)