The distance between the points (x, 21) and (4, -7) is 10*sqrt(3) . Find the sum of all possible values of x.
+36916 (x-4)^2 + (21- -7)^2 = (10 sqrt3)^2
x^2 - 8x + 800 = 300
x^2 - 8x + 500 = 0 quadratic formula or factoring shows x = 4 +- 22i summed = 8
