course 2, lesson 3-2 write an integer for each situation. 1. stock market down 56 points 2. a score...
TRANSCRIPT
Course 2, Lesson 3-2
Write an integer for each situation.
1. stock market down 56 points
2. a score of 3
3. a bank deposit of $25
Evaluate each expression.
4.
5.
6. What is the value of if k = −6 and m = −2
19
+12 2
k m
Course 2, Lesson 3-2
ANSWERS
1. −56
2. 3
3. 25
4. 19
5. 14
6. 4
WHAT happens when you add,subtract, multiply, and divide integers?
The Number System
Course 2, Lesson 3-2
Course 2, Lesson 3-2 Common Core State Standards © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
The Number System
• 7.NS.1 Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers; represent addition and subtraction on a horizontal or vertical number line diagram.
• 7.NS.1a Describe situations in which opposite quantities combine to make 0.
• 7.NS.1b Understand p + q as the number located a distance |q| from p, in the positive or negative direction depending on whether q is positive or negative. Show that a number and its opposite have a sum of 0 (are additive inverses). Interpret sums of rational numbers by describing real-world contexts.
• 7.NS.1d Apply properties of operations as strategies to add and subtract rational numbers.
The Number System
• 7.NS.3 Solve real-world and mathematical problems involving the four operations with rational numbers.
• 7.EE.3 Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies.
Mathematical Practices
1 Make sense of problems and persevere in solving them.
3 Construct viable arguments and critique the reasoning of others.
4 Model with mathematics
7 Look for and make use of structure.
Course 2, Lesson 3-2 Common Core State Standards © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
•To add integers with the same sign•To add integers with different signs
Course 2, Lesson 3-2
The Number System
Course 2, Lesson 3-2
The Number System
• opposites 2 and –2
• additive inverse
Add Integers with the Same Sign
Course 2, Lesson 3-2
The Number System
Words To add integers with the same sign, add their absolute values. The sum is:• positive if both integers are positive.• negative if both integers are negative.
Examples 7 + 4 = 11 −7 + (−4) = −11
Add Integers with Different Signs
Course 2, Lesson 3-2
The Number System
Words To add integers with the different signs, subtract their absolute values. The sum is:
• positive if the positive integer’s absolute value is greater.• negative if the negative integer’s absolute value is
greater.
Examples 9 + (−4) = 5 −9 + 4 = −5
How did what you learned today help you answer the
WHAT happens when you add,subtract, multiply, and divide integers?
Course 2, Lesson 3-2
The Number System
How did what you learned today help you answer the
WHAT happens when you add,subtract, multiply, and divide integers?
Course 2, Lesson 3-2
The Number System
Sample answers:• The sum of two positive integers is positive.• The sum of two negative integers is negative.• To find the sum of two integers with different signs,
subtract their absolute values and use the sign of the integer with the greater value.
Find the sum –3 + (– 5)and the sum – 3 + 5.
Then write a few sentences comparing and contrasting
the expressions.
Ratios and Proportional Relationships
The Number System
Course 2, Lesson 3-2