7th Grade Math

116 Integers

Chapter Study

Guide and Review

Key Vocabulary

absolute value

additive inverse

coordinate plane

graph

integer

negative integer

opposites

ordered pair

origin

positive integer

quadrant

x-axis

x-coordinate

y-axis

y-coordinate

Vocabulary Check

State whether each sentence is true or false.

If false, replace the underlined word or

number to make a true sentence.

1. Integers less than zero are positive
   integers.


2. The origin is the point at which the x-axis
   and y-axis intersect.


3. The absolute value of 7 is -7.


4. The sum of two negative integers is
   positive.


5. The x-coordinate of the ordered pair
   (2, -3) is -3.


6. Two integers that are opposites are also
   called additive inverses.


7. The product of a positive and a negative
   integer is negative.


8. The x-axis and the y-axis separate the
   plane into four coordinates.


9. The quotient of two negative integers is
   negative.

Key Concepts

Absolute Value (Lesson 1)

• The absolute value of a number is the distance of
  the number from zero on a number line.

Integer Operations (Lessons 2 and 3)

• To add integers with the same sign, add their
  absolute value. The sum is positive if both
  integers are positive and negative if both integers
  are negative.
  
  
  • 2 + (-3) = - 5
  
  
  
  


• To add integers with different signs, subtract their
  absolute values. The sum has the sign of the
  integer with the larger absolute value.
  
  
  • 7 + 1 = - 6 - 3 + 5 = 2
  
  
  
  


• To subtract an integer, add its opposite.
  
  
  • 2 - 3 = - 2 + (-3) or - 5
  
  
  
  


• The product or quotient of two integers with
  different signs is negative.
  6(-2) = - 12 - 10 ÷ 2 = - 5


• The product or quotient of two integers with
  the same sign is positive.
  
  
  • 4(-5) = 20 - 12 ÷ (-4) = 3
  
  
  
  

Be sure the following

Key Concepts are noted

in your Foldable.

Lesson 1

Integers and the

Coordinate PlaneCCC

K

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