What is 5-9 using a number line?

Answer 1

14

Answer 2

Whether you use a number line or an abacus or whatever, 5-9 = -4.

On a number line you start from 5 and move nine steps to the left: step 1 to 4, step 2 to 3, step 3 to 2, step 4 to 1 step 5 to 0, step 6 to -1, step 7 to -2, step 8 to -3 and step 9 to -4.

If you are more advanced, instead of 9 steps to the left, you could do 10 left and 1 right (since -9 = -10+1).