document.write( "Question 1043677: Find the dimensions and area of the largest rectangle that can be inscribed in a right angle triangle, whose sides have lengths of 9cm, 12cm and a hypotenuse of 15cm. \n" ); document.write( "
Algebra.Com's Answer #659021 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Find the dimensions and area of the largest rectangle that can be inscribed in a right angle triangle, whose sides have lengths of 9cm, 12cm and a hypotenuse of 15cm. \n" ); document.write( ": \n" ); document.write( "let x = the width of the rectangle \n" ); document.write( "let y = the length \n" ); document.write( ": \n" ); document.write( "Draw out a right triangle with the rectangle inscribed therein, x by y \n" ); document.write( "the height of the right triangle = 12 and the base = 9 \n" ); document.write( ": \n" ); document.write( "We are interested in the small right triangles adjacent the inscribed rectangle \n" ); document.write( "The tangent of the top angle = 9/12 which = \n" ); document.write( "Cross multiply \n" ); document.write( "12x = 9(12-y) \n" ); document.write( "12x = 108 - 9y \n" ); document.write( "x = 9 - \n" ); document.write( "similarly, the tangent of the base angle = 12/9 = \n" ); document.write( "Cross multiply \n" ); document.write( "9y = 12(9-x) \n" ); document.write( "9y = 108 - 12x \n" ); document.write( "y = 12 - \n" ); document.write( ": \n" ); document.write( "Area = xy \n" ); document.write( "replace y with (12- \n" ); document.write( "A = x(12- \n" ); document.write( "A = 12x - \n" ); document.write( "A quadratic equation, max occurs at the axis of symmetry; x=-b/(2a) \n" ); document.write( "x = \n" ); document.write( "x = \n" ); document.write( "x = +4.5 cm is the width of the rectangle with max area \n" ); document.write( ": \n" ); document.write( "Find y \n" ); document.write( "y = 12 - \n" ); document.write( "y = 12 - 6 \n" ); document.write( "y = 6 cm is length \n" ); document.write( ": \n" ); document.write( "Max area: 6 * 4.5 = 27 sq/cm \n" ); document.write( ": \n" ); document.write( "NOt sure if I explained this clearly, let me know. CK \n" ); document.write( " |