Determine Whether or Not $x = \frac { 6 } { 7 } \text { is a solution to } 3 ^ { 6 x - 3 } = 81 \text {. }$

Determine whether or not $x = \frac { 6 } { 7 } \text { is a solution to } 3 ^ { 6 x - 3 } = 81 \text {. }$