To find the roots, we need to factorize the quadratic expression
x² + 6x - 55 = 0
x² + 11x - 5x - 55 = 0
x(x + 11) - 5x - 55 = 0
x(x + 11) -5 (x + 11) = 0
(x - 5)(x + 11) = 0
Then solve the value of x
x - 5 = 0
x = 5
or
x + 11 = 0
x = -11
The roots are -11 and 5
Sum of the roots
sum = -11 + 5
sum = -6
The answer is option b
