In order to put these numbers on a number line, you need to draw a number line and then count backwards to find your answer.
The first thing to do is to draw a number line from -9 to 3.
Then look at the equation which is:
-8 - -9 = 1
-8 + 9 = 1
The two negatives become a positive.
Because the sign is positive, you will count backwards on the number line a total of 9 places. This will then take you to 1.
Find out more on number lines at https://brainly.com/question/24644930
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