document.write( "Question 998411: What adds to give you -35 but multiplies to give you -3800? \n" ); document.write( "
Algebra.Com's Answer #616187 by Theo(13342)![]() ![]() You can put this solution on YOUR website! a is one of the numbers \n" ); document.write( "b is the other number \n" ); document.write( "a + b = -35 \n" ); document.write( "a * b = -3800 \n" ); document.write( "from the first equation, solve for b in terms of a to get b = -a - 35 \n" ); document.write( "in the second equation, replace b with -a - 35 to get: \n" ); document.write( "a * (-a - 35) = -3800 \n" ); document.write( "remove parentheses to get: \n" ); document.write( "-a^2 - 35a = -3800 \n" ); document.write( "add 3800 to both sides of this equation to get: \n" ); document.write( "-a^2 - 35a + 3800 = 0 \n" ); document.write( "multiply both sides of this equation by -1 to get: \n" ); document.write( "a^2 + 35a - 3800 = 0 \n" ); document.write( "this is a quadratic equation that can be factored to get: \n" ); document.write( "a1 = 46.58002809 \n" ); document.write( "a2 = -81.58002809\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you know that:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a1 + b1 = -35 \n" ); document.write( "a2 + b2 = -35\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for b1 and b2 to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b1 = -81.58002809 \n" ); document.write( "b2 = 46.58002809\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a1 = 46.58002809 and b1 = -81.58002809 \n" ); document.write( "a2 = -81.58002809 and b2 = 46.58002809\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "what this says is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if a = 46.58..., then b = -81.58... \n" ); document.write( "if a = -81.58..., then b = 46.58...\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "these equaations satisfy the two equations we started with simultaneously.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "those equations are:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a + b = -35 \n" ); document.write( "a * b = -3800\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "we can graph these equations and we can then see the solution graphically.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "let x = a and y = b,\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you get x + y = -35 \n" ); document.write( "x * y = -3800\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for y in both equations to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "y = -35 - x \n" ); document.write( "y = -3800 / x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the intersections of the graph of these equations is our solution because that point is common to both equations.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the graph look like this:\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( " |