document.write( "Question 149714: Two square wire frames are to be constructed from a piece of wire 100 inches long. If the area enclosed by one frame is to be one-half the area enclosed by the other, find the dimensions of each frame. (Disregard the thickness of the wire.) \n" ); document.write( "
Algebra.Com's Answer #109839 by nerdybill(7384)![]() ![]() You can put this solution on YOUR website! Let x = side of smaller square \n" ); document.write( "and y = side of larger square \n" ); document.write( ". \n" ); document.write( "x^2 is the area of smaller square \n" ); document.write( "y^2 is the area of larger square \n" ); document.write( ". \n" ); document.write( "4x is the perimeter of smaller square \n" ); document.write( "4y is the perimeter of larger square \n" ); document.write( ". \n" ); document.write( "Since we have two unknowns, we need two equations: \n" ); document.write( "From: \"Two square wire frames are to be constructed from a piece of wire 100 inches long.\" we get: \n" ); document.write( "4x + 4y = 100 \n" ); document.write( "x + y = 25 (equation 1) \n" ); document.write( ". \n" ); document.write( "From: \"If the area enclosed by one frame is to be one-half the area enclosed by the other\" we get: \n" ); document.write( "x^2 = (1/2)y^2 (equation 2) \n" ); document.write( ". \n" ); document.write( "solving equation 1 for x: \n" ); document.write( "x + y = 25 \n" ); document.write( "x = 25 - y \n" ); document.write( ". \n" ); document.write( "plug the above into equation 2 and solve for y: \n" ); document.write( "x^2 = (1/2)y^2 \n" ); document.write( "(25-y)^2 = (1/2)y^2 \n" ); document.write( "625 - 50y + y^2 = (1/2)y^2 \n" ); document.write( "1250 - 100y + 2y^2 = y^2 \n" ); document.write( "1250 - 100y + y^2 = 0 \n" ); document.write( "y^2 - 100y + 1250 = 0 \n" ); document.write( ". \n" ); document.write( "From the \"quadratic equation\" you'll get: \n" ); document.write( "y = 85.36 \n" ); document.write( "x = 14.64 \n" ); document.write( ". \n" ); document.write( "Therefore the dimensions are: \n" ); document.write( "85.36 in by 85.36 in (larger square) \n" ); document.write( "14.64 in by 14.64 in (smaller square) \n" ); document.write( ". \n" ); document.write( "Details of the quadratic solution follows: \n" ); document.write( "
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