Hi Guys

I keep on doing something wrong when I simplify QC algebra questions, but I am not sure if there is a rule I am not following. I have two examples, both are from the homework from this video

Below I attach the questions and my working. I understand what the correct solutions are, but am not sure why my alternative method is not correct. Any assistance would be greatly appreciated!

Edited formatting, cropped picture

Hey so for the first question, x can be zero, since they haven’t mentioned that x is not equal to zero. So you are not allowed to divide by zero.(14)

For the second one(11), when you are taking a square root, you need to take booth, the positive and negative values. For example, if x=5, A is 9 and B is 49 and for x=-5, A is 49 and B is 9.

square root of (x-2)^2 can be +(x-2) and -(x-2).

Hope it helps.

Thank you sooo much - these were driving me nuts! Tricky conceptual applications!

Cheers

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