Question

1. add or subtract 3/x-3-5/x-2
2.add or subtract -5/x-3/-4/x+2

Answer 1

1.Is this the correct expression?\[-\frac{4x}{x+7}-\frac{8}{x+7} \]

Answer 2

yes

Answer 3

\[-\frac{4x}{x+7}-\frac{8}{x+7}=\frac{-4x-8}{x+7}\]

Answer 4

thanks

Answer 5

Have you tried #2?

Answer 6

no

Answer 7

2. \[\frac{3}{x-3}-\frac{5}{x-2}\]This is similar, but in order to continue, the denominators must be the same. What is the LCD?

Answer 8

i dont know

Answer 9

Well, here is a site that helps to understand the concept of LCD. In this case I think I would use (x-3)(x-2) as the LCD.\[\left( \frac{x-2}{x-2} \right)\frac{3}{x-3}-\left( \frac{x-3}{x-3} \right)\frac{5}{x-2}=\frac{3(x-2)-5(x-3)}{(x-2)(x-3)}\]Can you take it from here?

Answer 10

*here is the website: http://www.mathsisfun.com/least-common-denominator.html