Answer: B
Step-by-step explanation:
To isolate x, you divide both sides by 21
21x=7

x = 7/21
Simplify by dividing both the numerator and denominator by 7
x = 1/3
Since, 1/3 is not an option, B is the correct answer
Answer:
I think it would be 214
Step-by-step explanation:
34+34=68
68+34=102
102+34=154
154+60=214