Answer :
=a^3+-11a^2+-9a+99-0
=a^3+-11a^2+-9a+99+0
(a^3)+(-11a^2)+(-9a)+(99+0)
a^3 -11a^2+-9a+99 is your answer
=a^3+-11a^2+-9a+99+0
(a^3)+(-11a^2)+(-9a)+(99+0)
a^3 -11a^2+-9a+99 is your answer