17.x - 7 = 3 *


a. 3

b. 7

c. 10

d. 12

 


18. 9x + 3 = 39 *



a. 2

b. 4

c. 6

d. 12



19. 9n - 7 = 74 


a. 3

b. 6

c. 9

d. 12


20. 9x + 2 = 29 *


a. 8

b. 5

c. 3

d. 2

Read and solve. Choose the correct answer.


21. Mary is 2 years younger than her sister who is 4 years younger than their brother. Their total age is 26. How old is Mary's sister? What is the correct equation for the problem?



2x + 2 = 26

2x - 2 = 26

x = 26 - 2

x = 26 + 2

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