Incorrect answer on Brilliant?

Going through the problems I came across: How many roots does the following equation have? |x^2 - 11| = |x-8|

After initially figuring out the answer, I came up with 4. It said I was wrong, there were 2?

I spent the next 3 hours trying to try different ways and establish how they came out with the answer 2... I still can't, I'm sure that the answer is 4!

Am I completely missing something?

#Algebra #AbsoluteValue #Mistake

Easy Math Editor

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`2^{34}`	$2^{34}$
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Comments

Link to the question? Wolfram Alpha also gives the same.

Siddhartha Srivastava - 6 years, 4 months ago

If you spot any errors with a problem, you can “report” it by selecting the “dot dot dot” menu in the lower right corner. You will get a more timely response that way.

Calvin Lin Staff - 6 years, 4 months ago

Thanks for that, I've reported it and it has now been rectified.

Sheridan Halls - 6 years, 3 months ago

I can't see this 'dot dot dot' menu? I have come across a couple of errors and not been able to report them!

Daniel Ferguson - 6 years, 3 months ago

If you're referring to a community problem, it is located at the bottom just next to the number of solvers

If you are referring to the practice section, it is stated as "report problem" at the bottom

Calvin Lin Staff - 6 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$