Question 1113878:  Find the dimension of the largest rectangle that can be inscribed in the right triangle with sides 3, 4, and 5 if a side of the rectangle is on the hypotenuse of the triangle. 
 Answer by math_helper(2461)      (Show Source): 
You can  put this solution on YOUR website!   units  
  units
 
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The Workout (assumes the max rectangle will have 1/2 the area of the 3-4-5 triangle, which I do not prove here, but it has been proven elsewhere): 
Area of the 3-4-5 triangle is    sq units. 
 
Area of largest rectangle is 1/2 that of the triangle, or  3 sq units.
  
If the triangle is drawn with side=3 along the y-axis, side=4 along the x-axis, and the hypotenuse connecting the points (0,3) with (4,0),  then the corner of the rectangle that meets the x-axis is at (2,0) and the corner that meets the y-axis is at (0,3/2).
 
Thus the length of the rectangle is    units. 
and the width of the rectangle is    units. 
 
The picture below has blue lines drawn to help visualize the 3 pairs of congruent triangles.  Exactly 3 of the 6 form the rectangle.  
 
  
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