1-4 Multiplying and Dividing Integers

Aim: How can we Multiply and divide integers and to solve problems

involving integers? CCSS: 7.NS.2.a

Warm up:

Vocabulary Review:

Integers are the set of whole numbers and their ___________________

Simplify each expression:

1.-3 + (-3) =

2.-5 + (-5) + (-5) =

3.-2 + (-2) + (-2) =

Multiplying and Dividing Integers

Simplify :

1. -2 • 9 • (-5) =

2. -9 • 8 • (-2) =

A hiker descends 360 feet in 40 minute. What is the hiker’s change in elevation per minute?

A. -9ft/min B- - 1/9 ft/min C. 1/9 ft/min D. 9 ft/min

Evaluating Algebraic expressions

Evaluate:

1. pt + (p + t) ÷ r for p = 4, t = -2, and r = -3

2. 2x + xy ÷ z for x = -9, y = -5, and z = -3

Check your understanding:

Think, Turn and Talk What is the sign of each product? Explain

1. n • n where n is any nonzero number.

2. y • y • y , where y is any negative number.

3. At the museum your class breaks into groups of 3 for a scavenger hunt. There are 24 students in your class. How many groups form?

4. THINK: What integer divided by -5 equals -60?

Suppose x and y are positive and a and b are negative. What is the sign of each quotient?

1 x÷a 2. y÷b 3. x/y 4 . a/(x +y) 5. b + a / x

Geology: Scientist drill 40,230 ft into Earth’s crust. A. Write an integer to represent this depth

B. Estimation: Estimate the depth drilled, to the nearest mile

Exit Ticket

1.What is the sign of the sum of two negative integers?

2.What is the product of two negative integers?

3.If two integers have the same sign, what is the sign of their sum?

4.If two integers have the same sign, what is the sign of their quotient?