This is a common mistake I notice in my O level A-Math essential concepts revision workshop.

Solve the following equation:

First, you must **identify the type of question** since different types of question require different strategies.

It's a **different log-log** question.

**Strategy required**: Change base.

Change base formula used.

Reason for changing to base 2: Between changing to base 2 or x, we choose base 2 as x is an unknown, we choose not to work with THE unknown most of the time, don't we?

Since we observe that there is a common term (log2 x),

Did you **observe the ****fatal mistake**** **(It's #7 Common mistake in Logarithm?

The correct way to do the substitution would be:

Solve the quadratic equation for y. Substitute the value back to find x.

Remember to check for validity of answers.

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