Question

1. Solve 3x + 3 =21

A. X=5
B. X=6
C. X=18
D. X=36

2. Solve 3/2× - 4 = 16

A. X=20
B. X=13 1/3
C. X=15 1/3
D. 30

Answer 1

`1.\\\\3x+3=21\qquad|\text{subtract 3 from both sides}\\\\3x=18\qquad|\text{divide both sides by 3}\\\\\boxed{x=6}\to\boxed{B.}`

`2.\\\\(3)/(2)x-4=16\qquad|\text{add 4 to both sides}\\\\(3)/(2)x=20\qquad|\text{multiply both sides by 2}\\\\3x=40\qquad|\text{divide both sides by 3}\\\\x=(40)/(3)\\\\\boxed{x=13(1)/(3)}\to\boxed{B.}`

Answer 2

1.

3x + 3 = 21

3x = 21-3

3x = 18

x = 18/3

Therefore,
x = 6


So option ( B) is the correct one.


2.


`(3x)/(2) - 4 = 16 \\ (3x)/(2) = 16 + 4 \\ \\ (3x)/(2) = 20 \\ 3x = 20 * 2 \\ 3x = 40 \\ x = (40)/(3) = 13 (1)/(3)`


Therefore option (B) is the correct one here too.