Answer:
x = 207
Step-by-step explanation:
Using Pythagoras' identity in the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
([tex]\sqrt{x}[/tex] )² + 7² = 16²
x + 49 = 256 ( subtract 49 from both sides )
x = 207
