-- Posted by KRNsoccerplayer24 at 8:09 pm on Dec. 7, 2008 5x/8y  plus 7/6xy i got the LCD is 8y(6xy) is that right? somehow i got the wrong answer -- Posted by matto at 8:11 pm on Dec. 7, 2008 your denominators are 8y and 6xy 3x(8y) = 4(6xy) so 24xy = 24xy, i think that's your lcd -- Posted by Sector Corrupt at 8:13 pm on Dec. 7, 2008 5x/8y + 7/6xy 30x^2/48xy + 56/48xy = (30x^2 + 56)/48xy = (15x^2 + 28)/24xy so the lowest common denominator is like.. 24xy? -- Posted by KRNsoccerplayer24 at 8:17 pm on Dec. 7, 2008 Quote: from matto at 8:11 pm on Dec. 7, 2008 your denominators are 8y and 6xy 3x(8y) = 4(6xy) so 24xy = 24xy, i think that's your lcd whered you get 3x(8y)=4(6xy)? -- Posted by matto at 8:20 pm on Dec. 7, 2008 take the two denominators: 8y and 6xy and try to make them equal to each other with the simplest operations so if you multiply 3*8 and 4*6, you get 24, which is the same: 3(8y) =? 4(6xy) this is 24y = 24xy, now the only thing different is the x: 3x(8y) = 4(6xy) and this simplifies to 24xy you could also do 6x(8y) = 8(6xy) = 48xy, but this isn't the Least Common denominator.  24xy's the least common denominator. I'm bad at explaining this, if you have a specific question anymore ask