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For which real numbers $x$ is $\begin{bmatrix} -\sqrt{5}/4 \\\ x+1/4 \\\ 1/4 \end{bmatrix}$ a unit vector?

Select ALL that apply.

$\dfrac{1}{4}$

$\dfrac{1}{2}$

$\dfrac{1}{16}$

$-\dfrac{9}{4}$

$-1$

$-\dfrac{9}{16}$

$\dfrac{3}{2}$

$-\dfrac{3}{2}$