Name ________________________________________ Date __________________ Class __________________
LESSON
1-5
NOTES: Multiplying Rational Numbers
Problem 1
Multiply: −3(1.5)
Use a number line.
−3(1.5)
THINK:
of 1.5 units 3 jumps Start at 0. Jump which way?
Rule 1: A negative (−) times a positive (+) makes a negative (−).
The product will be negative, so jump left.
So, −3(1.5) = −4.5
Use Rule 1 to multiply.
1.
−2.2(4) ________
2.
−6(0.5) ________
3.
−1(9.9) ________
4.
−3.3(3) ________
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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Name ________________________________________ Date __________________ Class __________________
Problem 2
( 34 )
Multiply: −2 −
( 34 )
−2 −
THINK:
2 jumps of 3
unit 4
Rule 2: A negative (−) times a negative (−) makes a positive (+).
The product will be positive, so jump right.
( 34 ) = 1 24 = 1 21 .
So, −2 −
Use Rule 2 to multiply.
6(
−10 ) = ________
5
5.
−
6.
−4 −
7.
(− 41 ) (−16) =
( 37 ) =
________
________
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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