Which value of $y$ I should take?

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There are points in complex space. Among these points, there are

$z_{B} = \sqrt{3} - i$

$z_{C} = i$

$z_{E} = -\sqrt{3} - i$

The question says: Find $z_{H}$ where $\overrightarrow{HC}.\overrightarrow{EB} = 0$ and $||\overrightarrow{HC}|| = 3$

My solution:

So I did dot product between the two vectors $\overrightarrow{HC}$ and $\overrightarrow{EB}$

I found that $x_{H} = 0$

Then to find $y_{H}$:

||$\overrightarrow{HC}|| = 3$ means

$\sqrt{(y_{H} - 1)^{2}} = 3$

Here is the thing, that means it's absolute value

So

$\sqrt{(y_{H} - 1)^{2}} = \begin{cases} & \text{ } 3 \\ OR & \text{} - 3 \end{cases}$

That means $y_{H}$ is either $4$ or $-2$

So which value I take here?