document.write( "Question 1002096: I have been stuck to this question on my math exam..can you solve this for me?\r
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document.write( "Find the dimension of a rectangle with an area of 27 square meters, if the length of a rectangle is three more than twice the width.\r
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Algebra.Com's Answer #619089 by Theo(13342)![]() ![]() You can put this solution on YOUR website! area of a rectangle = length * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the length is equal to 3 more than twice the width.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the equation for that is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "length = 2 * width + 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "start with:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area = length * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "replace length with 2 * width + 3 to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area = (2 * width + 3) * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "simplify this to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "area = 2 * width^2 + 3 * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since the area = 27, then replace area with 27 to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "27 = 2 * width^2 + 3 * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "subtract 27 from both sides of this equation to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0 = 2 * width^2 + 3 * width - 27\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this is the same aqs:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2 * width^2 + 3 * width - 27 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this equation is in standard form of ax^2 + bx + c = 0.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "replace width with x and your equation becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2x^2 + 3x - 27 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "now it's easier to see that your equation is in the standard form of ax^2 + bx + c = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since it is in standard form, you can find a and b and c.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a is the coefficient of the x^2 term. \n" ); document.write( "b is the coefficient of the x term. \n" ); document.write( "c is the constant term.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in your equation of 2x^2 + 3x - 27 = 0, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a = 2 \n" ); document.write( "b = 3 \n" ); document.write( "c = -27\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "don't forget that you made x = width. \n" ); document.write( "you will need that fact later on.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "to factor the equation of 2x^2 + 3x - 27 = 0, use the quadratic formula.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the quadratic formula says that:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = (-b + or - sqrt(b^2-4ac)) / (2a)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this results in 2 possible answers.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = (-b + sqrt(b^2-4ac))/(2a) or: \n" ); document.write( "x = (-b - sqrt(b^2-4ac))/(2a)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when a = 2 and b = 3 and c = -27, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b^2 = 3^2 = 9\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "4ac = 4*2*-27) = -216\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b^2-4ac = 9-(-216) = 9+216 = 225\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "sqrt(b^2-4ac) = sqrt(225) = 15\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-b = -3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2a = 4\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = (-b + sqrt(b^2-4ac))/(2a) or: \n" ); document.write( "x = (-b - sqrt(b^2-4ac))/(2a) becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = (-3 + 15)/4 or: \n" ); document.write( "x = (-4 - 15)/4 which becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = 3 or: \n" ); document.write( "x = -4.5\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since x can't be negative, you are left with:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "now's the time to remember that x represents the width.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "go back to your original equation that said:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "27 = length * width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "since width = 3, this equation becomes 27 = length * 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for length to get length = 9.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you have length = 9 and width = 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "now's the time to confirm your solution satisfies the problem requirements.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "those are:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Find the dimension of a rectangle with an area of 27 square meters, if the length of a rectangle is three more than twice the width.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you found the dimensions.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "they are length = 9 and width = 3.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "an additional requirement is that length is equal to three more than twice the width.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the width is 3.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "twice the width is 6\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "length is 9 which is 3 more than 6.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "length is 3 more than twice the width so you have met that requirement.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you're solution is good.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the dimensions are:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "length = 9 \n" ); document.write( "width = 3\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |