“Recognizing Integers”

September, 2011

7th Grade Math

Math Innovations – Page 67

• What do you notice about the number line below?

• Brainstorm with your partners and be prepared to share one thing from your group.

• What you thought…

How did you do?

• Numbers to the right of 0 are positive

• Numbers to the left of 0 are negative

• Number line is symmetrical about 0

• Pairs of numbers are same distance from 0

• Extends infinitely• Numbers written below the

line• Numbers written below tick

mark, not above or below interval

• Positive numbers do not have a sign

Math Innovations – Page 67

• Draw a number line and label the tick marks from -10 to 10. – Check that your number line is straight– The intervals are evenly spaced– The numbers are written under the line– The numbers line up with the tick marks, not

the spaces. – If necessary, fix your number line to meet

these rules.• Compare your number line to another

student’s. How are your lines the same? How are they different? Explain.

Math Innovations – Page 67

• How can you tell by looking at a number line which numbers are larger?

• How far does the number line “actually” go in the positive direction? Negative direction?

• Can you name the LARGEST number that we could put on a number line? What direction would it be in?

• Can you name the SMALLEST number that we could put on a number line? What direction would it be in?

• Brainstorm with your partners what you believe are the three (3) most important things someone should know about the number line.

“Kiss My Math”

• This is how Danica views integers. She calls them “mintegers”.

• Let’s label the number line with negative fractions and decimals.

• Draw 3 number lines from -1 to 1.–Locate ½ and – ½–Locate 2/3 and – 2/3–Locate 5/8 and -5/8

– Remember…To label a number line, start with zero and move to the right (positive), then to the left (negative)• Symmetrical about 0

Math Innovations – Page 67

Things I need to know…

• Positive Numbers – Numbers greater than 0

• Negative Numbers – Numbers less than 0

1st 2nd Block

It’s Your Turn…Part I

• I have some number lines created and I want you to practice locating both positive and negative numbers on a number line.– Side #1 (Lesson 2.1 Number Lines)

Things I need to know…

• The further right on the number the _________ the value.

– Example #1: Compare 32,000,000 and 6,000,000* 32 million is farther right on the number line.* Therefore, 32 million is greater than 6 million

- Example #2: Compare -10 and -2* -2 is farther right on the number line.* Therefore, -2 is greater than -10

It’s Your Turn…Part II

• I have some number lines created and I want you to practice locating both positive and negative numbers on a number line.– Side #2 (Lesson Guide 2.1A Negative Fractions and

Decimals)

• We talk about signed numbers using their direction and magnitude.

– Direction – Tells whether the number has a positive direction (to the right of 0) or a negative direction (to the left of 0)

– Magnitude (AKA Absolute Value) – How far the number is from 0 on the number line. Absolute Value is shown as ||

– Examples: • Give the magnitude and direction of 18.• Give the magnitude and direction of -23.• Give the magnitude and direction of -4 ½.• Give the magnitude and direction of 6.785

Math Innovations

It’s Your Turn…Part III

• Give the magnitude and direction of each number below.a. -7.3b. -12c. 6 ¼d. -0.8e. f.

109

7

3115

2

It’s Your Turn…Part IV

• Give the absolute value of each number below.a. |-7.3|b. |-12|c. |6 ¼|d. |-0.8|

e. | |

f. | |

109

7

3115

2

How are your answers here similar to the magnitude you found on previous slide?

Homework:

• “Recognizing Integers” practice problems