[ Answer ]
![\boxed{One}](/tpl/images/0486/7543/a0f89.png)
[ Explanation ]
How Many Solutions To Equation ![\sqrt{X \ = \ 16}](/tpl/images/0486/7543/3eaad.png)
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Solve To Find Possibilities
Square Both Sides
= ![16^{2}](/tpl/images/0486/7543/1c713.png)
Expand
: x
Expand
: 256
Verify Solutions
X = 256 (True)
Answer - X = 256
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There is exactly one answer, therefore there is One Solution
![\boxed{[ \ Eclipsed \ ]}](/tpl/images/0486/7543/ae81a.png)