Question 1106989
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<U>Pythagoras says</U>:


    4^2 + x^2 = (x+1)^2

    16 + x^2 = x^2 + 2x + 1

    16 = 2x + 1

    2x = 16-1 =  15  ====>  x = {{{15/2}}} = 7.5.


<U>Answer</U>.  x = 7.5,  and the sides of the triangle are  4, 7.5 and 8.5  cm.
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It is well known &nbsp;(8,15,17) &nbsp;Pythagorean right-angled triangle.