The technically correct answer to the question as you posed it is "MQ is a line segment with endpoints M and Q". However, I suspect that you actually meant to ask "What is the measure of segment MQ?" which you might have abbreviated by saying "What is mMQ?".
mCM + mMQ = mCQ, so mMQ = mCQ - mCM.
Just substitute the given values and do the arithmetic.
John
My calculator said it, I believe it, that settles it
