Respuesta :

A) 45 - 3x = 18x

+ 3x

45 = 21x

/21

2 1/7 = x

B) 3x + 2/5 = 31

-2/5

3x = 30 3/5

/3

x = 10 1/5

C) 2z - 3/5 - z -6/4 = 3

Combine like terms

z - 2 1/10 = 3

+ 2 1/10

z = 5 1/10