Solve the logarithmic equation log₂(x - 1) = 4.

Step 1: Identify the logarithmic equation.

We are given:
log₂(x - 1) = 4

This means that the base 2 raised to the fourth power equals x - 1.

Step 2: Rewrite the equation in exponential form.

Using the relationship:
log_b(A) = c means b^c = A

we get:
2^4 = x - 1

Step 3: Evaluate the power.

2^4 = 16

So:
16 = x - 1

Step 4: Solve for x.

Add 1 to both sides:
x = 17

Step 5: Check the domain and solution.

The argument of a logarithm must be positive:
x - 1 > 0

For x = 17:
17 - 1 = 16 > 0

The solution is valid.

Therefore, x = 17.