p1 cie question

[cooldude]

why is root x always postive, for example why do we consider root 4=2 and not +/-2.

[astarmathsandphysics]

There are 2 roots. Why do you ask this

[cooldude]

There are 2 roots. Why do you ask this

because our book says this, for example when x^0.5-6-x
we get x=4,9
they say root x=3,2
and since 6-9=-3 they say that 9 does not satisfy the original equation as they are not considering root x=-3, as they say that root x=>0, so i am asking why is root x=>0?

[astarmathsandphysics]

Only because the question says or because x is b length for example:)