Let $r$ and $s$ be the roots of $x^2 - 6x + 2 = 0.$ Find $(r - s)^2.$
x^2 - 6x + 2 = 0
x^2 -6x + 9 = -2 + 9
(x - 3)^2 = 7 take both roots
x - 3 = ±√7
x = √7 + 3 or x = -√7 + 3
So ( r -s) = 2√7 = √28
So (r - s)^2 = 28
+23 
