y^2=x vs y=sqrt(x). Is they is or is they ain't the same thing.

[Jragon]

@dracoi

When I was in school, we learned to use the absolute value markers when solving equations like this.

So if you start with y^2 = x, you would actually want to convert it to |y| = sqrt(x) to avoid losing half of your possible outcomes. Because |-5| = 5, you retain the same graph, with a curve both above and below the x axis

Nobody else has mentioned this, so maybe it was just my teacher making this point.

This is true, but you’re no longer working with functions if you do this. Most of why we assume y=sqrt(x) takes the positive square root is because taking both results in a non-function. |y|=sqrt(x) (or even |y|=x) results in the same “problem”.