160 likes | 169 Views
7.NS.1 a. Understand that the additive inverse of a number is its opposite and their sum is equal to zero. Question?. Can you think of any number you can add to 4 to get 0?. Additive Inverse Property. What do you think this property means? Let’s look at the words individually.
E N D
7.NS.1 a. Understand that the additive inverse of a number is its opposite and their sum is equal to zero.
Question? • Can you think of any number you can add to 4 to get 0?
Additive Inverse Property • What do you think this property means? • Let’s look at the words individually. • 1st what does additive mean? • 2nd what is inverse? • Can you figure out what this property does?
Let’s practice • 1. What is the additive inverse of 8? • 2. Solve: (-9) + 9 = • 3. What is the additive inverse of (-2)? • 4. Solve: (-66) + 66 = • 5. What is the additive inverse of 8,964? • 6. Solve: (-771) + x = 0 • 7. What is the additive inverse of (-9,276)? • 8. Solve: 27 + (-27) = • 9. What is the additive inverse of (-12)? • 10. Solve: 0 + 9,276 =
Practice answers • 1. (-8) • 2. 0 • 3. 2 • 4. 0 • 5. (-8,964) • 6. 771 • 7. 9,276 • 8. 0 • 9. 12 • 10. 9,276
How can we use this property? • What if you see this problem. Could it help if you knew this property? -3 + 5 + (-5) Or 20 + (-20) + (8)
Adding integers • When adding integers with the same sign just add and keep the sign: • Examples: 6 + 3 = 9 is the same as (+6)+ (+3)= +9 and -4 + (-7) = -11 or -7 + (-4) = -11 (Do you recognize this property?)
Commutative property • Commutative property says that you can swap the order of two numbers when adding or multiplying and still get the same answer.
Adding integers with different signs • When adding integers with different signs REMEMBER THIS… Adding a negative is the same as subtracting a positive and Subtracting a negative is like adding a positive
Let’s examine this closer • Adding a negative is like subtracting a positive 11 + (-6) is the same as 11 – (6) 2 + (-3) is the same as 2 – (3) 5 + (-5) is the same as 5 - 5
Let’s examine this… • Subtracting a negative is like adding a positive 3 – (-4) is the same as 3 + (4) 8 – (-6) is the same as 8 + (6) 9 – (-10) is the same as 9 + (10)
Workbook practice • Volume 1 p. 204 p. 207 (1-10)