Review 7
Rational Numbers: Adding/Subtracting Integers Review
CCSS Standard
Prerequisite for 8.NS.1
Materials: Notes on Adding/Subtracting Integers on a number line (using multiplication rules to
eliminate double signs.
Homework worksheet: Adding/Subtracting Integers Worksheet
Suggested Lesson Structure:
 Go through notes which guide students to use multiplication rules to eliminate double
signs when necessary and then move along the number line to add and subtract
integers.
 Work through sample problems to allow students to have some guided practice.
 Give students some sample problems to work through individually. Compare and
discuss solutions.
 You may want to have students model the problems on the board.
Homework: Adding/Subtracting Integers Worksheet
Reference Materials:
Teacher Notes below
Have students copy into notebook.
Videos/Interactives:
http://www.geogebra.org/en/upload/files/english/Megan/Integers_NumberLine/Addition/I
nt_NumberLine_Addition.html
http://www.geogebra.org/en/upload/files/english/Megan/Integers_NumberLine/Subtracti
on/Int_NumberLine_Subtraction.html
http://teachers.henrico.k12.va.us/math/hcpsalgebra1/module2-1.html
Adding and Subtracting Integers using a Number Line
TEACHER COPY
Create at number line. Label it from -10 to 10. Identify the smallest and largest integer.
−5 + (−3)
(+) 𝑡𝑖𝑚𝑒𝑠(−) = (−)
1. Circle the starting number in the expression, label it and plot it on the number line.
2. Box the sign (or signs) that shows the direction in the expression and label with an
arrow above it showing the direction. Students must apply the multiplication rules
when there are two signs and re-write the expression so there is only one sign.
−5 − 3)
3. Box the single sign that shows the direction in the expression and label with an arrow
above it showing the direction.
4. Underline the number in the expression that represents the number of spaces you
move from the starting point.
5. From the starting point, record your movement on the number line and circle the
answer. Plot the start number. Use the number underline and move that number of
spaces based on the arrow. The number you land on is your answer.
3
−5 − 3
-8
-5
start
In your groups (pairs) repeat the above process for the following problem. Compare your work and make
sure you are in agreement.
6
−1 − (−6)
-1
0
1
2
3
4
5
Adding and Subtracting double signed integers
On a separate sheet of paper: A) copy each problem, B) Rewrite problem to eliminate the double sign (use
the rules from your notes), and C) Model each problem on a separate number line (Draw arrow to show
movement and direction).
1)
5)
9)
9 + (−7) =
−5 – 2 =
6 − |−3 | =
2) −7 + (−5) =
6) 9 – (−5) =
10) 14 − (−7) =
3) −5 + (−13) =
7) −8 + |− 4| =
4) −8 + (− 4) =
8) −20 + 5 =
Adding and Subtracting double signed integers
On a separate sheet of paper: A) copy each problem, B) Rewrite problem to eliminate the double sign (use
the rules from your notes), and C) Model each problem on a separate number line (Draw arrow to show
movement and direction).
1)
5)
9)
9 + (−7) =
−5 – 2 =
6 − |−3 | =
2) −7 + (−5) =
6) 9 – (−5) =
10) 14 − (−7) =
3) −5 + (−13) =
7) −8 + |− 4| =
4) −8 + (− 4) =
8) −20 + 5 =
Adding and Subtracting double signed integers
On a separate sheet of paper: A) copy each problem, B) Rewrite problem to eliminate the double sign (use
the rules from your notes), and C) Model each problem on a separate number line (Draw arrow to show
movement and direction).
1)
5)
9)
9 + (−7) =
−5 – 2 =
6 − |−3 | =
2) −7 + (−5) =
6) 9 – (−5) =
10) 14 − (−7) =
3) −5 + (−13) =
7) −8 + |− 4| ==
4) −8 + (− 4) =
8) −20 + 5 =
Adding and Subtracting double signed integers
On a separate sheet of paper: A) copy each problem, B) Rewrite problem to eliminate the double sign (use
the rules from your notes), and C) Model each problem on a separate number line (Draw arrow to show
movement and direction).
1)
5)
9)
9 + (−7) =
−5 – 2 =
6 − |−3 | =
2) −7 + (−5) =
6) 9 – (−5) =
10) 14 − (−7) =
3) −5 + (−13) =
7) −8 + |− 4| = =
4) −8 + (− 4) =
8) −20 + 5 =