SOLUTION: 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.

Algebra ->  Customizable Word Problem Solvers  -> Geometry -> SOLUTION: 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.      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



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) About Me  (Show Source):
You can put this solution on YOUR website!
+Length+=+5%2F2+ units
+Width+=+6%2F5+ units

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 +%281%2F2%29%2A4%2A3+=+6+ 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 +sqrt%282%5E2+%2B+%283%2F2%29%5E2%29+=+sqrt%2825%2F4%29+=+5%2F2+ units.
and the width of the rectangle is +3+%2F+%28%285%2F2%29%29++=+6%2F5+ 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.