A line and a circle intersect at $A$ and $B,$ as shown below. Find the distance between $A$ and $B$.
The circle is x^2 + y^2 = 20.
The line is y = -4.
x^2 + (-4)^2 = 20
x^2 + 16 = 20
x^2 = 4
x= 2 or x = -2
y = -4 y = -4
AB = 2- (-2) = 4
+1725 
