Answer
True
Work Step by Step
If $T: V \rightarrow W$ is an isomorphism, $\dim V=\dim W$
Then $R^n: \dim R^n=n\\
R^m: \dim R^m=m$
For $T:R^n \rightarrow R^M$ to be isomorphism, $m$ should be equal to $n$.
Hence, the statement is true.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.