document.write( "Question 476080: Two numbers that have a product of -840 and the sum is -22. \n" ); document.write( "
Algebra.Com's Answer #326945 by bucky(2189)![]() ![]() ![]() You can put this solution on YOUR website! Let the two numbers be x and y. \n" ); document.write( ". \n" ); document.write( "The product of the two numbers is -840. In equation form this is: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "The sum of the two numbers is -22. In equation form this is: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "In the second equation solve for one of the variables in terms of the other. For example solve for x by subtracting y from both sides of the equation. When you do this subtraction you get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Substitute the right side of this equation for x in the first equation. This substitution leads to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Multiply out the left side by multiplying y times each of the two terms in parentheses to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "add 840 to both sides of this equation and you have: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "To get this into standard quadratic form, multiply both sides (all terms) by -1 and the result is: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "You can solve this by using the quadratic formula, or you can factor it. The left side factors as shown: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Since you now know possible solutions for y, you can return to the second equation and solve for x. Using the second equation, substitute y = -42 and you get for x: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Add +42 to both sides and this becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "So one possible solution to this problem is x = 20 and y = -42 \n" ); document.write( ". \n" ); document.write( "Another possible solution occurs when y = +20. You can work this out by solving for x, but you will find that the answer for x is x = -42. \n" ); document.write( ". \n" ); document.write( "The answer now becomes apparent. One of the two numbers is -42 and the other is +20. (Either x = 20 and y = -42 or y = 20 and x = -42). \n" ); document.write( ". \n" ); document.write( "Hope this helps you to understand the process for solving this problem. \n" ); document.write( " |