# Math question

#### BioTic

Sin is 2/x. I use P theorm to get...
b²=x²-4.
Then get √(b²)=√(x²-4)
giving b=√(x²-4)

Why isn't the answer x-2 or x²-2 since we are taking square root of both sides?
Thanks

#### molarbear8895

If the values under the root were being multiplied or divoded you can simply remove the square with the root but if you are adding or subtracting you need to add/subtract then take the root of that. Since you have a variable you can't really go any further.
If you think about it P theorem would make no sense if you could just square both sides and have a+b=c

BioTic