The hypotenuse of the right-angled triangle has length . The square , whose side length is , is inscribed in the triangle as shown above (pictured red).
If is the longer leg of the triangle, and is the shorter leg, find the value of .
Hint : .
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I literally just spent 1 hour writing the solution and clicked "Have the solution checked by a pro" and it took me to the Brilliant^2 site and the solution is gone. I'm too lazy to write it all again, so I'll just write the main things:
From the given hint, you notice that the legs of the two triangles are proportional.
Solving the proportion you'll conclude that 12(a+b)=ab.
From the Pythagorean theorem, we know that a^2+b^2=1225. We also know that a 2 + b 2 = ( a + b ) 2 − 2 a b so we can re-write it as (a+b)^2-2ab=1225
That gives us a system/set of two equations. We add replacements for easier solving: ab=x and a+b=y
Now the set of equations looks like this: 1 2 y = x y 2 − 2 x − 1 2 2 5 = 0
Plugging in the x from the first one into the second one, we get y 2 − 2 4 y − 1 2 2 5 = 0 Solving this quadratic equation, we get that the only positive solution for y is 49. That makes x=588. That gives us a new set of equations. a × b = 5 8 8 a + b = 4 9 Solving this, we get b=28 and a=21 (because b>a). Finally, we have: b − a = 2 8 − 2 1 b − a = 7 . 0 0