document.write( "Question 186249: A rectangle is 4 times as long as it is wide. a second rectangle is 5 cm longer and 2 cm wider than the first. the are of the second rectangle is 270 square cm greater than the first. What are the dimensions of the original rectangle?
\n" );
document.write( "
\n" );
document.write( " \n" );
document.write( "
Algebra.Com's Answer #139700 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! A rectangle is 4 times as long as it is wide. a second rectangle is 5 cm longer and 2 cm wider than the first. the are of the second rectangle is 270 square cm greater than the first. What are the dimensions of the original rectangle? \n" ); document.write( ": \n" ); document.write( "Let x = width of the 1st rectangle: \n" ); document.write( ": \n" ); document.write( "\"A rectangle is 4 times as long as it is wide.\" \n" ); document.write( "4x = length of the 1st rectangle \n" ); document.write( "then \n" ); document.write( "4x^2 sq/cm = area of 1st rectangle \n" ); document.write( ": \n" ); document.write( "a second rectangle is 5 cm longer and 2 cm wider than the first.\" \n" ); document.write( "(4x + 5) = length of 2nd rectangle \n" ); document.write( "(x + 2) = width of 2nd rectangle \n" ); document.write( "then find the area of the 2nd rectangle \n" ); document.write( "FOIL:(4x+5)*(x+2) = 4x^2 + 8x + 5x + 10 = 4x^2 + 13x + 10 sq cm \n" ); document.write( ": \n" ); document.write( "the area of the second rectangle is 270 square cm greater than the first. \n" ); document.write( "4x^2 + 13x + 10 - 4x^2 = 270 \n" ); document.write( "4x^2 - 4x^2 + 13x = 270 - 10 \n" ); document.write( "13x = 260 \n" ); document.write( "x = \n" ); document.write( "x = 20 \n" ); document.write( ": \n" ); document.write( " What are the dimensions of the original rectangle? \n" ); document.write( "4(20) = 80 cm is the length \n" ); document.write( "80 by 20 is the dimensions of the original rectangle \n" ); document.write( "; \n" ); document.write( "; \n" ); document.write( "Check solution, find the area of both rectangles \n" ); document.write( "4(20) + 5 = 85 cm \n" ); document.write( "20 + 2 = 22 cm \n" ); document.write( "85 * 22 = 1870 sq cm area of 2nd rectangle \n" ); document.write( "and \n" ); document.write( "80 * 20 = 1600 sq cm area of 1st rectangle \n" ); document.write( ": \n" ); document.write( "1870 - 1600 = 270 confirms our solution \n" ); document.write( " \n" ); document.write( " |