[ Answer ]
[tex]\boxed{One}[/tex]
[ Explanation ]
How Many Solutions To Equation [tex]\sqrt{X \ = \ 16}[/tex]
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Square Both Sides
[tex](\sqrt{6})^{2}[/tex] = [tex]16^{2}[/tex]
[tex](\sqrt{x} )^{2}[/tex]: x
[tex]16^{2}[/tex]: 256
X = 256 (True)
Answer - X = 256
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There is exactly one answer, therefore there is One Solution
[tex]\boxed{[ \ Eclipsed \ ]}[/tex]