Question

M is between points C and Q. CM=17 and CQ=21. What is MQ?

Answer 1

sometimes it helps to draw it out...

(17)
C_______M_________Q
|___________________|
21

therefore, CM + MQ = CQ
17 + MQ = 21
MQ = 21 - 17
MQ = 4 <===

Answer 2

we know that

If M is between points C and Q

then

`CQ=CM+MQ`

`CM=17\ units\\ CQ=21\ units\\MQ=?`

Solve for MQ

`MQ=CQ-CM`

Substitute the values in the formula above

`MQ=21-17`

`MQ=4\ units`

therefore

the answer is

`MQ=4\ units`