For motion in a straight line you can use a + or – to indirection.
+10 m/s (velocity of 10 m/s to the right)
+10 m/s (velocity of 10 m/s to the right)
Note:+10 m/s may be written without the +, just as 10 m/s
Quantities, such as velocity, which have a direction as well as a magnitude (size), are called vectors.