What is the distance between 9 and −10 on the number line?

Answer 1

THE OLD NUMBER LINE! You start with the number line literally X axis before you learn the Y axis.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

__!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!___!

-12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12

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DISTANCE

19 spaces

or the easy way ---- 9- (-10)= 9 +10+19

Answer 2

| 9 - -10 | = | 9 + +10 | = | 19 | = 19