Find All Real Zeros of the Polynomial $f ( x ) = x ^ { 3 } + 3 x ^ { 2 } - 49 x - 147$

Multiple Choice

Find all real zeros of the polynomial $f ( x ) = x ^ { 3 } + 3 x ^ { 2 } - 49 x - 147$ and determine the mutiplicity of each.

A) $x = 7$ , multiplicity $2 ; x = - 3$ , multiplicity 1
B) $x = 7$ , multiplicity $1 ; x = - 7$ , multiplicity $1 ; x = - 3$ , multiplicity 1
C) $x = - 3$ , multiplicity $2 ; x = - 7$ , multiplicity 1
D) $x = - 7$ , multiplicity $1 ; x = 3$ , multiplicity $1 ; x = - 3$ , multiplicity 1
E) $\quad x = - 3$ , multiplicity 3