2.1+Adding+on+a+Number+Line+0910

Big Idea Negative numbers help us to model many real world situations. __Essential Question #2: How can I add integers?

A) Write the addition sentence illustrated by each figure. 1) The addition sentence is -4-3= -7. 2) The addition sentence is +4 - (-3)= 7 3) The addition sentence is -4 + 11= 7 4) The addition sentence is 5+(-8) = -3

B) Illustrate each addition problem on a number line, and give the answer. 1)



C) When you add two integers, does the order of the numbers make a difference? Illustrate your answer by showing each of these pairs of sums on a number line. 1) -5 + (+10) and +10 - (-5) 2) -4 + -6 and -6 + -4 3) +8 + -8 and -8 + +8



4) 6 + -7 and -7



2.1 Follow Up 1)you can think of the scoring in MathMania as follows: when a team answers a question correctly a positive integer is added to their score. When a team answers a question incorrectly a negative integer is added to their score. For each of the following situations write an addition sentence that will give the teams score. Assume each team starts with 0 points.

A) The brainiacs answer a 200 point question correctly and a 150 point question incorrectly. The addition problem is 200 + (-150) = 50 B) The aliens answer a 100 point question correctly a 100 point incorrectly and a 250 point correctly. The addition problem is 100 + (-100) + 250= 250 C) The prodigies answer a 50 point question incorrectly a 100 point incorrectly and a 250 point correctly. The addition problem is 50- (-100) +250=100

2) Illustrate each addition problem on a number line and give the answer. __



3) What happens when you add opposites? Explain how you know your answer. When you add opposites the sum will be always a zero. I know this because on a number line when adding opposites the arrows go back to 0.