document.write( "Question 505214: Together Sophie and Clarissa can paint a house in 6 days. It takes Clarissa 5 days less than Sophie to paint the house by herself. How many days does it take Sophie to paint the house by herself? \n" ); document.write( "
Algebra.Com's Answer #339817 by nerdybill(7384)![]() ![]() You can put this solution on YOUR website! Together Sophie and Clarissa can paint a house in 6 days. It takes Clarissa 5 days less than Sophie to paint the house by herself. How many days does it take Sophie to paint the house by herself? \n" ); document.write( ". \n" ); document.write( "Let x = time (days) it takes for Sophie to do it alone \n" ); document.write( "then \n" ); document.write( "x-5 = time it takes for Clarissa \n" ); document.write( ". \n" ); document.write( "6(1/x + 1/(x-5)) = 1 \n" ); document.write( "multiplying both sides by x(x-5): \n" ); document.write( "6(x-5 + x) = x(x-5) \n" ); document.write( "6(2x-5) = x(x-5) \n" ); document.write( "12x-30 = x^2-5x \n" ); document.write( "-30 = x^2-17x \n" ); document.write( "0 = x^2-17x+30 \n" ); document.write( "0 = (x-15)(x-2) \n" ); document.write( "x = {15, 2} \n" ); document.write( "the 2 won't make sense, throw it out leaving: \n" ); document.write( "x = 15 days (Sophie's time) \n" ); document.write( ". \n" ); document.write( "Clarissa: \n" ); document.write( "x-5 = 15-5 = 10 days\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |