Find the Zeros of the Quadratic Function by Completing the Square

Multiple Choice

Find the zeros of the quadratic function by completing the square. List the x-intercepts of the graph of the function.
- $$F ( x ) = x ^ { 2 } + 6 x - 40$$

A) $x = \sqrt { - 40 } , x = \sqrt { 40 }$
B) $x = - 30 , x = - 10$
C) $x = - 4 , x = 10$
D) $x = 4 , x = - 10$