Lesson Number Systems

Number Systems: Operations with Rational Numbers (1)

MGSE7.NS.1a Show that a number and its opposite have a sum of 0 (are additive inverses). Describe situations in which opposite quantities combine to make 0. For example, your bank account balance is -$25.00. You deposit $25.00 into your account. The net balance is $0.00. 

COPY THE NOTES IN YOUR NOTEBOOK!!!

Types of Numbers

• Natural Numbers ( 1, 2, 3, 4, 5...)

• Whole Numbers ( 0,1,2,3,4,5...) Includes 0 and all natural numbers

• Integers (..., -3, -2, -1, 0, 1, 2, 3...)

• Rational Numbers ( All Natural, Whole, Integers, fractions, and decimal numbers) can be written as a ratio

• Irrational Numbers- Can not be written as a ratio. Ex. Pi

Absolute Value

• distance a number is from zero along a number line

• Simply put, is just asking you how far away -4 is from zero.

• Since distance is always a positive number (you can't travel "negative" steps, just steps in a different direction), the result of absolute value is always positive.

Additive Inverse

• Another name for Additive Inverse is "Opposite"

• Example 4 and -4

• Opposites are an equal distance from zero.

• Their sums are zero

Open Ended

Choose one word from the image that describes a negative number.

Open Ended

Choose one word from the image that describes a positive number.

Multiple Choice

The lowest recorded temperature in Antarctica was about 90°F below zero. The highest recorded temperature in Antarctica was about 15°F. Which integer represents the highest recorded temperature in Antarctica?

• -90

• 15

• -15

• 90

Multiple Choice

What is the result of adding 3 to −3?

• -6

• 0

• 9

• -9

Multiple Choice

What is the result of adding 20 to −20?

• -40

• 20

• 0

• -20

Multiple Choice

An elevator is on the 10th floor. It goes down 6 floors and then up 4 floors. What floor is the elevator on now?

• 6th floor

• 7th floor

• 8th floor

• 9 floor