Why, since |k| = sqrt((k^2)), is k not also equal to -(1/2)?

[jonathan.s.kim]

From the Equations, Inequalities & VIC's guide (pg 167), where it talks about exponential (or geometric) sequence, it has an example which is solving for a variable k like so:
3 = k^2(12)
3/12 = k^2
k^2 = 1/4
k = 1/2
Why, since |k| = sqrt((k^2)), is k not also equal to -(1/2)?

The next sentence that follows this example states that "k can be greater than 1, less than 1, and even less than 0."

[RonPurewal]

absolutely correct. in that example, k should be able to equal either 1/2 or -1/2.

we'll fix that!

(by the way, you posted this thread in the wrong folder. i'll move it for you.)