Answer:
(x+5)(x-11)=0
Explanation:
x^2-6x-55=0
[Multiply the coefficient of last and first, (55*1=55) and find such a factor of it such that its product is equal to the product of coefficient of last and first and such that it adds or subtracts(11-5=6)(depending on the sign of last coefficient) up to the coefficient of middle term]
x^2-11x+5x-55=0
x(x-11)+5(x-11)=0
(x+5)(x-11)=0