Subtracting Integers on a Number Line How to

Subtracting Integers on a Number Line

How to subtract using a number line • Place a circle on the number line to represent the first number in the problem. • Since this is subtraction, the second number will tell you how much to take away. – This is the opposite of addition. • A positive second number means you should move to the left. • A negative second number means you should move to the right. • The number you end on is the answer.

Example 1 O Model 5 - 4 using a number line. O Start at 5 on the number line. O Take away 4, or move 4 spaces to the left since the second number is positive. – 4 5 -4=1

Example 2 • Model 5 – 8 • Start at 5 on a number line. • Take away 8, or move 8 spaces to the left since the second number is positive. – 8 5 - 8 = -3

Example 3 • Model 5 – (-4) • Start at 5 on the number line. • Take away -4, or move 4 spaces to the right since the second number is negative. – (-4) 5 – (-4) = 9

Example 4 • Model -3 - 4 on a number line. – 4 -3 - 4 = -7

Example 5 • Model -1 - (-6) on a number line – (-6) -1 – (-6) = 5

Example 6 • Model 4 - 10 on a number line – 10 4 - 10 = -6

Example 7 • Model -8 - (-12) on a number line – (-12) -8 – (-12) = 4

Example 8 • Model -2 - 6 on a number line – 6 -2 - 6 = -8

Example 9 • Model 3 - (-4) on a number line – (-4) 3 – (-4) = 7

Example 10 • Model -7 – (-7) on a number line – (-7) -7 – (-7) = 0
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