Write a Polynomial for the Width of the Rectangle $x ^ { 3 } + 3 x ^ { 2 }$

Multiple Choice

Write a polynomial for the width of the rectangle.
-Write a polynomial for the width of the rectangle.

A) $x ^ { 3 } + 3 x ^ { 2 }$
B) $x + 9 x ^ { 2 }$
C) $x + 3$
D) $3 x ^ { 3 } + 6 x ^ { 2 }$