Calculation integers with the same sign using models

From KNILT

Lesson # 2: Adding integers (with the same sign)

Integers1.gif

Objectives

  1. Understand how to utilise models to add integers with the same sign
  2. Evaluate integer addition bug using mental math
  3. Develop methods for using integer tiles
  4. Develop existent life situations that model expressions

Warm-Up

  • State the definition of an integer and give three examples.
  • Use integer tiles to add the following integers:
  1. - 8 + three
  2. -6 + 6
  3. xiii + -viii

Answers to Warm-Up

Calculation integers with the same (negative) sign

We desire to use integer tiles again to add integers that have the same sign. So, both numbers are negative or both numbers are positive.

Let's first with adding two negative numbers. Employ your integer tiles to represent the expression...

-8 + -6 - 8 + -6.jpg


Steps

  • i. Arrange your integer tiles.
  • 2. How many cipher pairs tin nosotros make? Zero Pair Answer
  • 3. What is the answer to -8 + -6? -8 + -six Answer

Utilise your integer tiles to represent:

  • 4. -4 + -5
  • v. Tin can you do -xx + -15 without using your integer tiles? -20 + -fifteen Answer
    • Question: What is the "sign" (positive or negative) before the number 15 in question #five? Answer to sign of number 15


Stopthink1.jpg

When you are adding numbers with the same sign, what are you really doing? Answer

Can you think of a real life situation with your banking company account that tin can stand for calculation to negative integers? Share here

Adding Integers with the same (positive) sign

Y'all already know how to do this!

  • six. ) 4 + 8 = 12
  • 7. ) 19 + 25= 44
  • 8. ) 25 + 18 + 30 = 73
    • Question: What is the "sign" (positive or negative) before the number 30 in question #eight? Answer to sign of number 30


Here are the "rules" for adding integers with the same or different signs. Don't memorize them! These should exist used to help you explain your method.

  • Let'due south employ some mental math! Solve the following problems using mental math...
  1. -viii + -9
  2. -fifteen + -6
  3. 50 + 36
  4. -200 + -fifty

Answers to mental math bug

Assessment

Endeavor out these websites to do all of your new skills for calculation integers with the same and different signs.

  • [1]
  • [2] <-- This website uses models to help yous add!

Share one thing you lot have learned on this wiki page from Lesson # two.

Good job gold ribbon.png

Navigate

  • 1. Adding integers with different signs using models
  • 3. Subtracting integers using models
  • 4. Multiplying integers using models
  • Portfolio for Models: A Case Study for Instructional Tools
  • ETAP 623 Autumn 2010