document.write( "Question 1173233: Hey can you please help me with this word problem ASAP? Five times my age augmented by twice my sisters age is equal to sixty-four. Likewise, triple her age decreased by twice my age is equal to one. How old were each of us last year? \n" ); document.write( "
Algebra.Com's Answer #798425 by Theo(13342)![]() ![]() You can put this solution on YOUR website! let x = your age. \n" ); document.write( "let y = your sister's age.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "5 times your age plus 2 times your sister's age = 64 \n" ); document.write( "the equation for that is 5x + 2y = 64\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "3 times her age minus 2 times your age = 1 \n" ); document.write( "the equation for that is 3y - 2x = 1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for x in the first equation as shown below. \n" ); document.write( "start with 5x + 2y = 64. \n" ); document.write( "subtract 2y from both sides of the equation to get: \n" ); document.write( "5x = 64 - 2y \n" ); document.write( "divide both sides of the equation by 5 to get: \n" ); document.write( "x = (64 - 2y) / 5\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "replace x in the second equation with this to get: \n" ); document.write( "3y - 2x = 1 becomes: \n" ); document.write( "3y - 2 * (64 - 2y) / 5 = 1 \n" ); document.write( "multiply both sides of this equation by 5 to get: \n" ); document.write( "15y - 2 * (64 - 2y) = 5 \n" ); document.write( "simplify to get: \n" ); document.write( "15y - 128 + 4y = 5 \n" ); document.write( "combine like terms to get: \n" ); document.write( "19y - 128 = 5 \n" ); document.write( "add 237 to both sides of this equation to get: \n" ); document.write( "19y = 133 \n" ); document.write( "solve for y to get: \n" ); document.write( "y = 133/19 = 7\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "replace y with 7 in the equation of 5x + 2y = 64 to get: \n" ); document.write( "5x + 14 = 64 \n" ); document.write( "subtract 14 from both sides of the equation to get: \n" ); document.write( "5x = 50 \n" ); document.write( "solve for x to get: \n" ); document.write( "x = 50/5 = 10\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you have x = 10 and y = 7\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "confirm by replacing x and y in both original equations to get: \n" ); document.write( "5x + 2y = 64 becomes 5 * 10 + 2 * 7 = 64 which becomes 50 + 14 = 64 which becomes 64 = 64 which is true. \n" ); document.write( "3y - 2x = 1 becomes 3 * 7 - 2 * 10 = 1 which becomes 21 - 20 = 1 which becomes 1 = 1 which is true.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you were 10 years old and she was 7 years old this year.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your solution is that you were 9 years old and she was 6 years old last year.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |