You can
put this solution on YOUR website! log3 14 + log 3x = log3 42
Apply logarithmic law: log a + log b = log ab -- provided their base is the same
In our case,
log3 14 + log 3x = log3 42
becomes
log3 14x = log3 42
Remove the logarithmic function from both sides of the equation
14x = 42
x = 3