document.write( "Question 251660: The product of two two-digit numbers is 1484. The product of their units digits is 24 and the product of their tens digits is 10. The two numbers can be? \n" ); document.write( "
Algebra.Com's Answer #183388 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Here's another way to do this. \n" ); document.write( ":\r \n" ); document.write( "\n" ); document.write( "The product of two two-digit numbers is 1484. \n" ); document.write( " The product of their units digits is 24 and the product of their tens digits is 10. \n" ); document.write( " The two numbers can be? \n" ); document.write( ": \n" ); document.write( "1st two digit number 10a + b \n" ); document.write( "2nd two digit number 10c + d \n" ); document.write( ": \n" ); document.write( "\"The product of two two-digit numbers is 1484.\" \n" ); document.write( "(10a + b)&(10c + d) = 1484 \n" ); document.write( "FOIL \n" ); document.write( "100ac + 10ad + 10bc + bd \n" ); document.write( ": \n" ); document.write( "\"The product of their units digits is 24\" \n" ); document.write( "b * d = 24 \n" ); document.write( ": \n" ); document.write( "\"the product of their tens digits is 10.\" \n" ); document.write( "a * c = 10 \n" ); document.write( "We know that a is 5 and c is 2 or vice versa \n" ); document.write( ": \n" ); document.write( "In the 1st equation, we find we can replace bd with 24 and ac with 10 \n" ); document.write( "100(10) + 10ad + 10bc + 24 = 1484 \n" ); document.write( "1000 + 10ad + 10bc + 24 = 1484 \n" ); document.write( "10ad + 10bc + 1024 = 1484 \n" ); document.write( "10ad + 10bc = 1484 - 1024 \n" ); document.write( "10ad + 10bc = 460 \n" ); document.write( "Simplify, divide by 2 \n" ); document.write( "5ad + 5bc = 230 \n" ); document.write( ": \n" ); document.write( "Assume a=2, c=5 \n" ); document.write( "2(5d) + 5(5b) = 230 \n" ); document.write( "10d + 25b = 230 \n" ); document.write( "10d = 230 - 25b \n" ); document.write( "d = 23 - 2.5b \n" ); document.write( " Only two single digit integer solutions to this equation: \n" ); document.write( "b=8; d=3 (the only pair that satisfy eq: b * d = 24) \n" ); document.write( "and assuming; a=2; c=5 \n" ); document.write( "therefore: \n" ); document.write( "28, 53 can be the numbers \n" ); document.write( ": \n" ); document.write( "check: 28 * 53 = 1484\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |