document.write( "Question 255278: The length of a rectangle is x + 4
\n" );
document.write( "The width of a rectangle is x - 1
\n" );
document.write( "The perimeter is 46 cm\r
\n" );
document.write( "\n" );
document.write( "Calculate the length of the diagonal of the rectangle\r
\n" );
document.write( "
\n" );
document.write( "\n" );
document.write( "Please help?! \n" );
document.write( "
Algebra.Com's Answer #187547 by jsmallt9(3758)![]() ![]() ![]() You can put this solution on YOUR website! If we know the length and width of a rectangle we can use the Pythagorean Theorem to find the diagonal. So we will start by finding the length and width. \n" ); document.write( "We should know that the perimeter of a rectangle is the sum of the two lengths and the two widths. We are told that the perimeter is 46 and that the length is x+4 and the width is x-1. So: \n" ); document.write( "46 = x+4 + x+4 + x-1 + x-1 \n" ); document.write( "We can solve this for x. Simplifying the right side we get: \n" ); document.write( "46 = 4x + 6 \n" ); document.write( "Subtracting 6 from each side we get: \n" ); document.write( "40 = 4x \n" ); document.write( "Dividing both sides by 4 we get: \n" ); document.write( "10 = x \n" ); document.write( "So the length, x+4, is 14 and the width, x-1, is 9. The length and width of a rectangle and the diagonal of a rectangle form a right triangle with the diagonal as the hypotenuse. So we can use the Pythagorean Theorem to find the length of the diagonal. If d is the length of the diagonal then: \n" ); document.write( " \n" ); document.write( "Simplifying the right side we get: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Solving for d we get: \n" ); document.write( "d = +- \n" ); document.write( "Since d is the length of the diagonal, we will discard the negative value. So the length of the diagonal is \n" ); document.write( " \n" ); document.write( " |