Question 1108310
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<pre>
From the left right-angled triangle you have this Pythagorean equation

x^2 + h^2 = 6^2.        (1)


From the right right-angled triangle you have this Pythagorean equation

(6-x)^2 + h^2 = 4^2.    (2)


Subtract eq(2) from  eq(1). You will get

x^2 - (6-x)^2 = 36 - 16,

x^2 - 36 + 12x - x^2 = 20,

12x = 20 + 36 = 56.


=======>  x = {{{56/12}}} = {{{14/3}}}.
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Solved.