document.write( "Question 370040: If the product of two consecutive integers is decreased by 20 times the greater integer. The result is 442. Find the integers. \n" ); document.write( "
Algebra.Com's Answer #263832 by jsmallt9(3758)![]() ![]() ![]() You can put this solution on YOUR website! Consecutive integers are 1 apart from each other. So if \n" ); document.write( "x = the first integer \n" ); document.write( "then \n" ); document.write( "x+1 = the next integer \n" ); document.write( "The product of two consecutive integers: \n" ); document.write( "x*(x+1) \n" ); document.write( "The product of two consecutive integers is decreased by 20 times the greater integer: \n" ); document.write( "x*(x+1) - 20*(x+1) \n" ); document.write( "The product of two consecutive integers is decreased by 20 times the greater integer [is} 442: \n" ); document.write( "x*(x+1) - 20*(x+1) = 442 \n" ); document.write( "Now that we have translated the problem into an equation we can solve it. First we simplify each side: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "This is a quadratic equation so we want one side to be zero. So we'll subtract 442 from each side: \n" ); document.write( " \n" ); document.write( "Now we factor (or use the Quadratic Formula): \n" ); document.write( "(x-33)(x+14) = 0 \n" ); document.write( "From the Zero Product Property we know that this (or any) product can be zero only if one (or more) factors is zero. So: \n" ); document.write( "x-33 = 0 or x+14 = 0 \n" ); document.write( "Solving these we get: \n" ); document.write( "x = 33 or x = -14 \n" ); document.write( "These are not consecutive integers. But they are not supposed to be! \"x\" is the first of the two integers. x+1 is the other integer. So we have two sets of answers, one for when x = 33 and the other for when x = -14: \n" ); document.write( "33 and 34 \n" ); document.write( "or \n" ); document.write( "-14 and -13 \n" ); document.write( " \n" ); document.write( " |