Add and Subtract a Positive Number

Transcription

1 SS NS 2.1G7.NS.1.b Add, subtract, Understand multiply, p + q as and the divide number with located decimals; a distance add q with from p, in the positive or negative direction depending on whether q is positive or negative. Show negative integers; subtract positive integers from negative that a number and its opposite have a sum of 0 (are additive inverses). nterpret sums of rational numbers integers; by describing and verify real-world the reasonableness contexts. of the results. UNDRLYNG SKLLS AND ONS: basic facts; meaning of negative numbers SS G7..3 Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and Add and Subtract a ositive Number Subtract a positive number: go left. You can use a number line to show positive and negative numbers. When you add a positive number, you look to the right and move forward. o subtract a positive number, you look to the left and move forward. subtract add Add a positive number: go this way. he first number is where you start from. x a m p x a m p l l 1 Find 2 5. Look at the number line. Start at 2. You need to add 5. Face right. he second addend is positive, so move forward 5 spaces. You end up at +3. So, add 5 Find 1 6. On the number line, start at 1. You need to subtract 6. Face left. he number you are subtracting is positive, so move forward 6 spaces. SL Associates, nc. All rights reserved. subtract 6 You end up at 7. So, page 76 hapter 7 Lesson 2

2 R A SL Associates, nc. All rights reserved. 25. he temperature was 2. hen it rose 6 degrees he temperature was 2 F. hen it fell 6 degrees. ircle the correct choice. xplain how you decided F 27. Laara had a balance of $56 on her charge account. She paid off $30. A $56 $30 $86 $56 $30 $86 B $56 $30 $26 D $56 $30 $ risha said, When you add a positive number to another number, you can never get a result that is less than 0. Sandi said, You can get a result that is less than zero, but the result is always greater than what you started with. Who is right? xplain your reasoning. Sandi is right, risha is not. f you start with a negative number and add a smaller positive number, you can get a negative result. hapter 7 Lesson 2 page 77

3 R A at home! he temperature was 5. hen it rose 8 degrees he temperature was 5 F. hen it fell 8 degrees. ircle the correct choice. xplain how you decided F 27. Mia had a balance of $43 on her bank account. She paid off $25. A $43 $25 $68 $43 $25 $68 B $43 $25 $18 D $43 $25 $ Lynn said, When you add a negative number to another number, you can never get a result that is greater than 0. Sandi said, You can get a result that is greater than zero, but the result is always less than what you started with. Who is right? xplain your reasoning. Sandi is correct. f she starts with 2 and adds 4, she gets 2 which is less than 4. f she starts with 2 and adds any number, she will have 2 less each time. page 52 Home Resource and Homework hapter 7 Lesson 2 SL Associates, nc. All rights reserved.

4 R A SL Associates, nc. All rights reserved. 25. he temperature was 2. hen it rose 6 degrees he temperature was 2 F. hen it fell 6 degrees. ircle the correct choice. xplain how you decided F 27. Laara had a balance of $56 on her charge account. She paid off $30. A $56 $30 $86 $56 $30 $86 B $56 $30 $26 D $56 $30 $ risha said, When you add a positive number to another number, you can never get a result that is less than 0. Sandi said, You can get a result that is less than zero, but the result is always greater than what you started with. Who is right? xplain your reasoning. Sandi is right, risha is not. f you start with a negative number and add a smaller positive number, you can get a negative result. hapter 7 Lesson 2 Student Book age page 77

5 R A at home! he temperature was 5. hen it rose 8 degrees he temperature was 5 F. hen it fell 8 degrees. ircle the correct choice. xplain how you decided F 27. Mia had a balance of $43 on her bank account. She paid off $25. A $43 $25 $68 $43 $25 $68 B $43 $25 $18 D $43 $25 $ Lynn said, When you add a negative number to another number, you can never get a result that is greater than 0. Sandi said, You can get a result that is greater than zero, but the result is always less than what you started with. Who is right? xplain your reasoning. Sandi is correct. f she starts with 2 and adds 4, she gets 2 which is less than 4. f she starts with 2 and adds any number, she will have 2 less each time. page 52 Home Resource and Homework hapter 7 Lesson 2 SL Associates, nc. All rights reserved.