7th Grade Math

Lesson 2B Add and Subtract Integers 91

Examples 1–7 Add.

1. 
   
   
   
   • 6 + (-8) 2. 4 + 5 3. - 3 + 10
   
   
   
   


2. 
   
   
   
   • 15 + 8 5. 7 + (-11) 6. 14 + (-6)
     77 - 17 + 20 + (-3) 8. 15 + 9 + (-9) 9. - 4 + 12 + (-9)
   
   
   
   

Example 8 10. MONEY Sofia owes her brother $25. She gives her brother the $18 she

earned dog-sitting. Write an addition expression to describe this

situation. Then find the sum and explain its meaning.

= Step-by-Step Solutions begin on page R1.

Extra Practice begins on page EP2.

Examples 1–7 Add.

11. 
    
    
    
    • 22 + (-16) 12. - 10 + (-15) 13. 6 + 10 14. 17 + 11
    
    
    
    


12. 18 + (-5) 16. 13 + (-19) 17. - 19 + 24 18. - 12 + 10


13. 21 + (-21) + (-4) 20. - 8 + (-4) + 12 21. - 34 + 25 + (-25)


14. 
    
    
    
    • 16 + 16 + 22 23. 25 + 3 + (-25) 24. 7 + (-19) + (-7)
    
    
    
    

Write an addition expression to describe each situation. Then find each

sum and explain its meaning.

Example 8

25. SCUBA DIVING Lena was scuba diving 14 meters below the surface of the
    water. She saw a nurse shark 3 meters above her.


26. PELICANS A pelican starts at 60 feet above sea level. It descends 60 feet to
    catch a fish.
    2727 FINANCIAL LITERACY Stephanie has $152 in the bank. She withdraws $20.
    Then she deposits $84.


27. FOOTBALL A quarterback is sacked for a loss of 5 yards. On the next play,
    his team loses 15 yards. Then the team gains 12 yards on the third play.

B 29. GRAPHIC NOVEL Find the total profit or loss for each color of T-shirt.

We are creating

T-shirts to

be sold for

homecoming!

We a

T-shi

be so

home

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