Understanding The Basics INTEGERS ! Understanding The Basics Grade 8 Mathematics Brought to you by: Mr. Barry / 8200Math

What’s Next ? What we have here is a short, mini-quiz on integers. I’ll start by giving you the rules to review … Next you’ll get a series of questions to solve .. Finally, I’ll give you the answers to make sure you got all the correct solutions! Remember, there aren’t any tricks here … memorize the rules and you’ll do fine!

What R The Rules ? ADDITION: IF THE SIGNS ARE THE SAME, ADD THE NUMBERS AND KEEP THAT SIGN IF THE SIGNS ARE DIFFERENT, SUBTRACT THE NUMBERS AND TAKE THE SIGN OF THE NUMBER WITH THE GREATER ABSOLUTE VALUE

What R The Rules ? SUBTRACTION: ALWAYS CHANGE THE MINUS TO PLUS AND CHANGE THE SIGN OF THE NEXT NUMBER, THEN USE YOUR ADDING RULE.

What R The Rules ? MULTIPLICATION & DIVISION: MULTIPLY OR DIVIDE AS USUAL, THEN CHECK THE SIGNS OF THE NUMBERS – IF THE SIGNS ARE THE SAME, THE ANSWER IS ALWAYS POSITIVE IF THE SIGNS ARE DIFFERENT, THEN THE ANSWER IS ALWAYS NEGATIVE.

Now what?? You need to memorize the rules and then try the following sample questions. Solve these on scrap paper and then check your answers as you work your way through this slide presentation. GOOD LUCK !

Compute the following addition problems: - 8 + 24 = 43 + ( - 27 ) = - 3 + ( - 11 ) = - 8 + 15 + ( - 12 ) = 21 + ( - 17 ) + 8 + ( - 9 ) = 15 + ( - 15 ) =

Solve the following subtraction problems: 23 – ( - 11 ) = - 16 – 24 = 34 – 57 = - 8 – ( - 19 ) = 63 – ( - 77 ) = - 36 – ( - 22 ) =

Solve the following multiplication problems: - 12 ( - 25 ) = - 4 16 = - 8 x 15 = ( - 4 ) 3 = ( - 2 )( - 3 )( - 4 ) = ( 4 )( - 11 )( 2 ) =

Solve the following division problems:

R You Ready 2 See How U Did ? Please remember – U need to memorize the basic rules for adding, subtracting, multiplying, and dividing.

ADDITION ANSWERS - 8 + 24 = subtract / different signs = + 16 - 3 + ( - 11 ) = add / same signs = - 14 - 8 + 15 + ( - 12 ) = group the #s /add the positives, add the negatives, then subtract the 2 answers … [ - 20 + 15 ] = - 5 21 + ( - 17 ) + 8 + ( - 9 ) = group the #s like example 4 … [ - 26 + 29 ] = + 3 15 + ( - 15 ) = subtract / different signs = 0

Remember – U need to rewrite every subtraction problem! Subtraction Answers … Remember – U need to rewrite every subtraction problem! 23 – ( - 11 ) = 23 + 11 = (add/same signs) = 34 - 16 – 24 = - 16 + ( - 24 ) = (add/same signs) = - 40 34 – 57 = 34 + ( - 57 ) = (subtract/different signs) = - 23 - 8 – ( - 19 ) = - 8 + 19 = (subtract/different signs) = + 11 63 – ( - 77 ) = 63 + 77 = (add/same signs) = + 140 - 36 – ( - 22 ) = - 36 + 22 =(subtract/different signs) = -14

Multiplication Answers - 12 ( - 25 ) = (same signs = +) + 300 - 4 16 = (different signs = -) = - 64 - 8 x 15 = (different signs = -) = - 120 ( - 4 ) 3 = (- 4 x – 4 x – 4) <next, remember the even / odd rule … 3 neg. = - answer> - 64 ( - 2 )( - 3 )( - 4 ) = <even/odd rule again … > <3 neg. = - answer> = - 24 ( 4 )( - 11 )( 2 ) = <even/odd rule again … > <1 neg. = - answer> = - 88

Division ! + 3 - 16 + 53 + 16 + 250 The same rule as multiply … Same signs = positive / Different signs = negative + 3 - 16 + 53 + 16 + 250

That’s It Folks ! I hope you did well Return to these questions / practice makes perfect Memorize the rules … if you don’t memorize ‘em now, you will struggle all year with positive and negative numbers! If you don’t understand why my answer is different from yours you can email me at: 8200math@gmail.com

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