# Math Help - More rational expressions File attached

1. ## More rational expressions File attached

More rational expressions. I am trying to understand this but...

Find the LCD for the given and convert each into an equivalent rational expression with teh LCD as the denominator.

4 , 5x
---- --------
x-y 2y-2x

I factored what could be to get

4 , 5x
---- --------
x-y 2(y-x)

now I think the LCD is 2(y-x)

The next problem is

3 2b -5
---------- , --------- , -----------
4b^2 - 9 2b + 3 2b^2-3b

I factored what I could (I think)

3 2b -5
---------- , --------- , -----------
4b^2 - 9 2b + 3 b(2b-3)

2. Originally Posted by Chester
More rational expressions. I am trying to understand this but...

Find the LCD for the given and convert each into an equivalent rational expression with teh LCD as the denominator.

4 , 5x
---- --------
x-y 2y-2x

I factored what could be to get

4 , 5x
---- --------
x-y 2(y-x)

now I think the LCD is 2(y-x)
Good.

The next problem is

3 2b -5
---------- , --------- , -----------
4b^2 - 9 2b + 3 2b^2-3b

I factored what I could (I think)

3 2b -5
---------- , --------- , -----------
4b^2 - 9 2b + 3 b(2b-3)
You can do more.

$\frac{3}{(2b+3)(2b-3)},\frac{2b}{2b+3}, \frac{-5}{b(2b-3)}$
Therefore the LCD is,
$b(2b+3)(2b-3)$