Solve the Problem $3 \sqrt { 2 } \mathrm { ft }$

Multiple Choice

Solve the problem.
-Find the value for x in the cube. Use exact values.

A) $3 \sqrt { 2 } \mathrm { ft }$
B) $9 \mathrm { ft }$
C) $3 \sqrt { 3 } \mathrm { ft }$
D) $3 \mathrm { ft }$