Take the natural log of both sides:

Use the multiplication identity: ln(ab) = ln(a) + ln(b)

Use the exponent identity:

Distribute the ln(18)

Put all the terms with x in them on one side by subtracting x*ln(2) from both sides:

Put all the terms without x in them on the other side by adding ln(18) to both sides:

Factor out an x:

Divide by the coefficient of x, which is [ln(18)-ln(2)]

Use additive identity of logarithms to see that

Use subtraction identity to see that

Now you've solved for x,