1 / 20

Unit 1: Rational Numbers

Unit 1: Rational Numbers. Topic: Review of Integers. Math 9 Miss Wilkinson Monday, September 9. What is an Integer?. Integers : Includes all of the Whole Numbers (called Natural Numbers). Recall: Integers are positive and negative whole numbers including zero .

teigra
Télécharger la présentation

Unit 1: Rational Numbers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Unit 1: Rational Numbers Topic: Review of Integers Math 9 Miss Wilkinson Monday, September 9

  2. What is an Integer? • Integers: Includes all of the Whole Numbers (called Natural Numbers). • Recall: Integers are positive and negative whole numbers including zero. • Never a fraction or decimal! • Integers are whole numbers that describe opposite ideas in mathematics.

  3. Positive Integers • right of zero • valued greater than zero. • Express ideas of up, a gain or a profit. • The sign for a positive integer is (+), however the sign is not always needed. • Meaning +3 is the same value as 3. Examples: Speed limits, time,golf scores.

  4. Negative Integers • left of zero • valued less than zero. • Express ideas of down or a lose. • The sign for a negative integer is (-). This sign is always needed. • Examples: thermometer, altitude, sports (+/-)

  5. Integers on a Number Line • Writing numbers down on a Number Line makes it easy to tell which numbers are bigger or smallerand how far they are away in relation to each other. • Ex: Plot 2, -6, 0 and-8 on a number line. Which number is larger?

  6. Comparing Integers Do we remember the symbols < and > ? • 1 < 3 means that 1 is LESS THAN 3 • 9 > 2 means that 9 is GREATER THAN 2 • 8 ___ 2 • 3 ___ 5 • -1 ___ -3 • -5 ____ 3

  7. Addition of Integers • Adding two positives results in a positive number. • Adding two negatives results in a negative number • Adding a negative is like subtracting a positive. Remember +(-n)=-n and –(+n)=-n where n is a number. • Math Term: SUM Examples: a) 15 + (-4) b) (+4) + (-15) c) (-8) + (-2)

  8. Subtraction of Integers • Subtracting a negative is like adding a positive. • Math Term: DIFFERENCE Examples: a) 8 – (-4) b) 8 – 4 c) -8 –4

  9. The Rules • Addition and Subtraction of integers can be put into two rules: Rule #1 Two like signs become a positive sign +(+) ex: 3+(+2) = 3 + 2 = 5 −(−)ex: 6−(−3) = 6 + 3 = 9 Rule #2 Two unlike signs become a negative sign +(−) ex: 7+(−2) = 7 − 2 = 5 −(+) ex: 8−(+2) = 8 − 2 = 6

  10. Multiplication of Integers In multiplication, we are trying to find the product of two integers. First step is to multiply the numbers like regular. Math Term: PRODUCT

  11. Understand So, why do two negatives make a positive? • If I say "Eat!" I am encouraging you to eat (positive) • But if I say "Do not eat!" I am saying the opposite (negative). • Now if I say "Do NOT not eat!", I am saying I don't want you to starve, so I am back to saying "Eat!" (positive).

  12. Examples • (3)(-4)= -12 c) (-4)(-1) WHY? 3 sets of 4 -4+-4+-4 = -8+-4 = -12 b) (7)(8)(-2) d) (6)(-3)(0)

  13. Division of Integers • Division of integers is the opposite of multiplying integers, but the rules are the same. • Do we remember how to long divide? • Math Term: QUOTIENT

  14. Examples: a)-20 ÷ -4 c) -12 ÷ 3 b) 64 ÷ -8 d) -156 ÷ 9

  15. Order of Operations • We now know how to add, subtract, multiply and divide integers • What happens when there is more than one of the above operations in the same problem? • When simplifying an expression that has more than one operation symbol, there is a special order you must follow. • Has anyone heard of BEDMAS?

  16. ÷ × • Brackets always come first. Solve what is inside the brackets • Exponents always come second. • D/M- when working with multiplication and division, you do whichever comes first as you work from left to right. If multiplication comes first, do it before dividing. • A/S-same as multiplication and division-when working with addition and subtraction, you do whichever comes first as you work from left to right.

  17. Examples • 8 x 2 -3 c) (5+2)(1-9) • 2x 4 -3 + 7 d) 22 + 7 x 2

  18. Assignment • I want to see where each and every one of your understanding is in regards to the review of integers and operations on integers (addition, subtraction, multiplication, division). • Please complete this short assignment at the end of class and hand it in to Miss Wilkinson.

More Related