document.write( "Question 80995: the length of a rectangle is 5 cm more than 3 times its width. If the area of the rectangle is 95 cm^2, find the dimensions of the rectangle to the nearest thousandth \n" ); document.write( "
Algebra.Com's Answer #58103 by praseenakos@yahoo.com(507)![]() ![]() You can put this solution on YOUR website! The length of a rectangle is 5 cm more than 3 times its width. If the area of the rectangle is 95 cm^2, find the dimensions of the rectangle to the nearest thousandth.\r \n" ); document.write( "\n" ); document.write( "ANSWER:\r \n" ); document.write( "\n" ); document.write( "Assume that width of the rectangle is 'x' cm.\r \n" ); document.write( "\n" ); document.write( "Then 3 times width = 3x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "5 cm more than 3 times its width = (3x + 5)cm\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is given that its length is 5cm more than 3 times its width\r \n" ); document.write( "\n" ); document.write( "So length of the rectangle = (3x + 5) cm.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Area of a rectangle is given by the formula, A = length * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Here area is given that 95 cm^2\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So we can write it as,\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "90 = (3x + 5 ) * x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "==> 95 = 3x * x + 5 * x\r \n" ); document.write( "\n" ); document.write( "==> 95 = 3x^2 + 5x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Subtract 95 from both sides of the equation, then we will obtain a quadratic equation.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "==> 95 - 95 = 3x^2 + 5x - 95\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "==> 0 = 3x^2 + 5x - 95\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "3x^2 + 5x - 95 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "We can solve this equation using quadratic formula.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "standard form of a quadratic equation is,\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ax^2 + bx + c = 0 ---------------(2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "By quadratic formula, the solution is given by,\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Comparing (1) and (2) we have,\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a = 3, b = 5 and c = -95\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "so the solution is,\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = (-4 + 34.14)/6 or x = (-4 - 34.13 )/6\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = 30.14/6 or x = -38.13/6\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "( since negative values are not admisible here)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "==> x = 5.023 cm\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So width of the rectangle is 5.023 cm.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "so width = 5.023 cm.\r \n" ); document.write( "\n" ); document.write( "and length = 3x + 5 = 3 * (5.782) + 5 = 15.069 + 5 = 20.069 cm\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the dimenstions of the given rectangle:\r \n" ); document.write( "\n" ); document.write( "length = 20.069 cm and\r \n" ); document.write( "\n" ); document.write( "Width = 5.023 cm.\r \n" ); document.write( "\n" ); document.write( "To check your answer, multiply length with breadth, then you will get 95 approximately.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Hope you understood.\r \n" ); document.write( "\n" ); document.write( "Regards.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Praseena.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |