document.write( "Question 1197235: Is it possible to have a rectangular property which has perimeter of 78 m and an area of 395m^2? \n" ); document.write( "
Algebra.Com's Answer #830427 by math_tutor2020(3817)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "L = length \n" ); document.write( "W = width\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "P = perimeter of a rectangle \n" ); document.write( "P = 2(L+W) = 2L+2W\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Replace P with the stated perimeter 78 and let's isolate L \n" ); document.write( "P = 2L+2W \n" ); document.write( "78 = 2L+2W \n" ); document.write( "78/2 = 2L/2+2W/2 \n" ); document.write( "39 = L+W \n" ); document.write( "L = 39-W\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "A = area of a rectangle \n" ); document.write( "A = LW \n" ); document.write( "A = (39-W)W \n" ); document.write( "A = -W^2+39W\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Plug in the stated area A = 395 \n" ); document.write( "I'll replace each W with x \n" ); document.write( "A = -W^2+39W \n" ); document.write( "395 = -x^2+39x \n" ); document.write( "395+x^2-39x = 0 \n" ); document.write( "x^2-39x+395 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Use the quadratic formula to solve for x. \n" ); document.write( "Use a = 1, b = -39, c = 395. \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( "The discriminant \n" ); document.write( "The two roots of x^2-39x+395 = 0 are complex numbers in the form a+bi where \n" ); document.write( "If your teacher hasn't covered complex or imaginary numbers just yet, then ignore this subsection. \n" ); document.write( "The summary is that x^2-39x+395 = 0 has no real solutions.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since x^2-39x+395 = 0 has no real solutions, this means we cannot have a rectangle with perimeter 78 meters and area 395 square meters. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |