Answer:
n = 0
Step-by-step explanation:
Multiply parenthesis by 3 and get:
1.) 18 + 9n = 5n + 18 + 3n
Then cancel the equal terms:
9n = 5n + 3n
Collect like terms:
9n = 8n
Move variable to the left:
9n - 8n = 0
n + 0
Plugin the value of 0 into x:
3 (6 + 3 x 0) = 18
5 x 0 + 3 x 0 + 18 = 18
*If the plugged in value have the same result than the answer is correct because 18 + 18.