document.write( "Question 584734: Sue is five years youger than Candice.The product of thier ages two years from now will be eighteen more than twice the product of their ages a year ago.How old are Sue and Candice now? \n" ); document.write( "
Algebra.Com's Answer #372887 by Theo(13342) You can put this solution on YOUR website! let s represent sue's age now. \n" ); document.write( "let c represent candice's age now. \n" ); document.write( "your answer is: \n" ); document.write( "s equals 4 and c equals 9. \n" ); document.write( "2 years from now s will be equal to 6 and c will be equal to 11. \n" ); document.write( "1 year ago s was equal to 3 and c was equal to 8. \n" ); document.write( "the problems states that the product of their ages 2 years from now will be 18 more than twice the product of their ages a year ago. \n" ); document.write( "using the solutions found, this equation becomes: \n" ); document.write( "6 * 11 = 18 + 2 * 3 * 8 which simplifies to: \n" ); document.write( "66 = 18 + 48 \n" ); document.write( "simplify this to get: \n" ); document.write( "66 = 66 which confirms the numbers are good. \n" ); document.write( "how did we get it? \n" ); document.write( "today sue is 5 years younger than candice. \n" ); document.write( "this translates to: \n" ); document.write( "s = c - 5 \n" ); document.write( "2 years from now the product of sue's age and candice's age will be: \n" ); document.write( "(s + 2) * (c - 5 + 2) which becomes: \n" ); document.write( "(s + 2) * (c - 3) \n" ); document.write( "1 year ago, the product of sue's age and candice's age was: \n" ); document.write( "(s - 1) * (c - 5 - 1) which became: \n" ); document.write( "(s - 1) * (c - 6) \n" ); document.write( "the equations we will be working with are: \n" ); document.write( "(s + 2) * (c - 3) which is the product of their ages 2 years from now. \n" ); document.write( "(s - 1) * (c - 6) which is the product of their ages 1 year ago. \n" ); document.write( "the formula we will be using is: \n" ); document.write( "product of their ages 2 years from now is equal to 18 plus [ 2 times the product of their ages 1 year aqo ]. \n" ); document.write( "this becomes: \n" ); document.write( "(s+2) * (c-3) = 18 + [ 2 * (s-1) * (c-6) ] \n" ); document.write( "you need to multiply these out to get: \n" ); document.write( "sc - 3s + 2c - 6 = 18 + 2 * (sc - 6s - c + 6) \n" ); document.write( "simplify this to get: \n" ); document.write( "sc - 3s + 2c - 6 = 18 + 2sc - 12s - 2c + 12 \n" ); document.write( "add 12s and 2c to both sides of this equation to get: \n" ); document.write( "sc - 3s + 12s + 2c + 2c - 6 = 18 + 2sc + 12 \n" ); document.write( "simplify this by combining like terms to get: \n" ); document.write( "sc + 9s + 4c - 6 = 30 + 2sc \n" ); document.write( "subtract 2sc from both sides of this equation to get: \n" ); document.write( "-sc + 9s + 4c - 6 = 30 \n" ); document.write( "add 6 to both sides of this equation to get: \n" ); document.write( "-sc + 9s + 4c = 36 \n" ); document.write( "since s = c - 5, substitute for s in this equation to get: \n" ); document.write( "-((c-5)*c) + 9*(c-5) + 4c = 36 \n" ); document.write( "simplify to get: \n" ); document.write( "-c^2 + 5c + 9c - 45 + 4c = 36 \n" ); document.write( "combine like terms to get: \n" ); document.write( "-c^2 + 18c - 45 = 36 \n" ); document.write( "add 45 to both sides of this equation to get: \n" ); document.write( "-c^2 + 18c = 81 \n" ); document.write( "add c^2 and subtract 18c from both sides of this equation to get: \n" ); document.write( "0 = c^2 - 18c + 81 which is the same as: \n" ); document.write( "c^2 - 18c + 81 = 0 \n" ); document.write( "factor this quadratic equation to get: \n" ); document.write( "(c-9) * (c-9) = 0 \n" ); document.write( "this results in c = 9. \n" ); document.write( "since s = c - 5, this results in s = 4 \n" ); document.write( "your answer is s = 4 and c = 9 as shown and confirmed way up top at the beginning of this exercise.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |