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2-3 Addition of Rational Numbers(pgs 63-70) 2-4 Subtraction of Rational Numbers (pgs71-76). Assignment 2-3/68-69/3-63 M3 2-4/74-75/3-54M3. Vocab. Additive Inverses (2-3) Two rational numbers with a sum of_______. (examples: -4.2 and 4.2 , and ) Note:
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2-3 Addition of Rational Numbers(pgs 63-70)2-4 Subtraction of Rational Numbers (pgs71-76) Assignment 2-3/68-69/3-63 M3 2-4/74-75/3-54M3
Vocab Additive Inverses (2-3) • Two rational numbers with a sum of_______. (examples: -4.2 and 4.2 , and ) Note: All represent the same quantity
Think of the number line for adding integers • Add a positive integer by moving to the ___________on the number line • Add a negative integer by moving to the ________ on the number line • Subtract an integer by adding its opposite
Rules for Addition of Integers 1)To add integers having the ___________sign, _________ the absolute value of each number. __________the same sign. (SAK) Same-Add-Keep 2) To add integers with ____________signs, _____________the smallest absolute value from the largest. Use the sign of the number with the ________________absolute value and. (DSL) Different-Subtract- Larger 3) Subtract an integer by ____________________its opposite. (then follow 1 or 2) 4) Watch out! The negative of a negative is the opposite positive number. -(-a) = +a
Examples • Find the additive inverse • 5.7 2) 3) –(-6)
Add or Subtract (For HW you must show finding common denominator for all fractions) • -10 + -15 (SAK or DSL?) 5) -3 – 8 (change then SAK or DSL) 6) (-5) + 4 +(-12) + 13 (Hint: Combine + and – first)
7) 8) • -50 – 3 10)
-2 –(-5x) + 8x – 3x – (-6) 12) Joe has $86 in his account and writes a check for $95. How much is in his account? • It was 12°F at 6:00 pm at midnight it was -3°F, how much did the temperature change?