Transparency 4

Click the mouse button or press the Click the mouse button or press the Space Bar to display the answers.Space Bar to display the answers.

Objective

Multiply Integers

Vocabulary

None

Multiply Integers

1. Same Sign

Positive Answer

2. Different Signs

Negative Answer

3 4 = 12

-3 -4 = 12

3 -4 = -12

-3 4 = -12

Example 1 Multiply Integers with Different Signs

Example 2 Multiply Integers with Different Signs

Example 3 Multiply Integers with Same Signs

Example 4 Multiply Integers with Same Sings

Example 5 Use Integers to Solve a Problem

Answer: –54

Opposite Signs

Multiply numbers without signs9 6

54 Opposite signs , negative answer-

Write problem

9 ( - 6 ) Draw arrows to signs

Identify signs

1/5

Answer: –28

1/5

Answer: –35

Opposite SignsMultiply numbers without signs

5 7

35-

Write problem

- 5 7 Draw arrows to signs

Identify signs

Opposite signs , negative answer

2/5

Answer: –24

2/5

Answer: 63

Same Signs

Multiply numbers without signs7 9

63+

Write problem

7 9 Draw arrows to signs

Identify signs

Same signs, positive answer

3/5

Answer: 20

3/5

Answer: 32

Same Signs

Multiply numbers without signs4 8

32+

Write problem

- 4 ( - 8 ) Draw arrows to signs

Identify signs

Same signs, positive answer

4/5

Answer: 14

4/5

ELEVATORS An elevator takes passengers from the ground floor of a shopping mall down to the underground parking garage. If it travels at a rate of 5 feet per second, where will it be in relation to the ground floor after 2 seconds?

To find the location of the elevator after 2 seconds, you can multiply 2 by the amount of change per second, –5 feet.

2 ( - 5 )

5/5

Answer: –10 feet

Opposite Signs

Multiply numbers without signs2 5

10-

2 ( - 5 ) Write problem

Draw arrows to signs

Identify signs

Opposite signs , negative answer

5/5

INVESTMENTS Mr. Green has invested in a stock whose price is decreasing at a rate of $3 per day. What will be the change in the price of the stock after 5 days?

Answer: –$15

*

5/5