Step-by-step explanation:
Combine like terms on the right side,
42= 3x+6.
Subtract 6 from each side
36=3x
Divide each side by 3
x=12, which is our lowest integer.
The next two integers we find with 12+2=14 and 12+4=16. Or just simply take the next two even integers. Thus, 12+14+16=42.
Hope this helps.