document.write( "Question 128173: It takes Tom 3 hours less to paint a fence than Jim. If the two boys work together, they can paint the fence in 2 hours. How many hours would each boy, working alone, need to paint the fence? \n" ); document.write( "
Algebra.Com's Answer #93852 by marcsam823(57)![]() ![]() ![]() You can put this solution on YOUR website! 1. Set up the variables: \n" ); document.write( "Let x = # hours it takes Jim to paint the fence alone \n" ); document.write( "Let x - 3 = # hours it takes Tom to paint the fence alone \n" ); document.write( "Let 1/x = amount of the fence painted by Jim in 1 hour \n" ); document.write( "Let \n" ); document.write( "\n" ); document.write( "2. Set up the equation(s) \n" ); document.write( "In 1 hour the two boys paint \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "In 2 hours the two boys paint: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "3. Find the common denominator: (x)(x-3)= \n" ); document.write( " \n" ); document.write( "4. Multiply both sides of the equation by (x^2 - 3x): \n" ); document.write( " \n" ); document.write( "5. Combine like terms: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "6. Factor and solve for x: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Since we have two answers we need to see which one makes sense by plugging each into our equations: \n" ); document.write( "Jim can paint a fence in x = 1 hours \n" ); document.write( "Tom can paint a fence in x-3 = -2 hours \n" ); document.write( "We must reject this answer because time can never be a negative value. \n" ); document.write( "Substitute x = 6: \n" ); document.write( "Jim can paint the fence in \n" ); document.write( "Tom can paint the fence in \n" ); document.write( "This is the answer we are looking for.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |