7th Grade Math

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

Extra Practice begins on page EP2.

Examples 1–4 Solve each equation. Check your solution.

8. 3 x + 1 = 10 9. 5 x + 4 = 19 10. 2 t + 7 = - 1


9. 6 m + 1 = - 23 12. - 4 w - 4 = 8 13. - 7 y + 3 = - 25


10. 
    
    
    
    • 8 s + 1 = 33 15. - 2 x + 5 = - 13 16. - 3 + 8 n = - 5
    
    
    
    


11. 5 + 4 d = 37 18. 14 + ^23 p = 8 19. 25 + ^11
    12
    y = 47

BAR DIAGRAM Write an equation. Use a bar diagram if needed. Then

solve the equation.

Example 5

20. BICYCLES Cristiano is saving money to buy a new bike that costs $189.
    He has saved $99 so far. He plans on saving $10 each week. In how
    many weeks will Cristiano have enough money to buy the new bike?


21. PETTING ZOOS It costs $10 to enter a petting zoo. Each cup of food to feed
    the animals is $2. If you have $14, how many cups of food can you buy?

Solve each equation. Check your solution.

B 22. 2 r - 3.1 = 1.7 23. 4 t + 3.5 = 12.5 24. 10 = b(2 ÷ 3)

25. 5 w + 9.2 = 19.7 26. 16 = 0.5r - 8 27. n + 9 ÷ 3 = 14


26. GRAPHIC NOVEL Refer to the graphic novel frame below. Jamar figured
    that they need to spend $39 for popcorn. Write and solve an equation to
    find how many movies they can purchase.

Help us figure how

many movies we

can buy. Refer

to the beginning

of the chapter.

2929 TEMPERATURE Temperature is usually measured Alaska Record Low

Temperatures (°F) by Month

January - 80

April - 50

July 16

October - 48

on the Fahrenheit scale (°F) or the Celsius

scale (°C). Use the formula F = 1.8C + 32 to

convert from one scale to the other.

a. Convert the temperature for Alaska’s

record low in July to Celsius. Round to

the nearest degree.

b. Hawaii’s record low temperature is -11°C. Find the difference in

degrees Fahrenheit between Hawaii’s record low temperature and the

record low temperature for Alaska in January.

Lesson 3B Multi-Step Equations 233

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