Question

PLEASE HELP GUYS!?
Find the lowest common denominator of 9/x+7-2/x
:)

Answer 1

It is not clear what you intended.

You wrote this: \(\dfrac{9}{x} + 7 - \dfrac{2}{x}\). Is that what you intended?

Answer 2

no the x+7 is together sorry.

Answer 3

$$\tt \frac{9}{x}+7-\frac{2}{x}\\
$$
Find lowest denominator that goes with every factor:
$$
\frac{9}{x}+\frac{7x}{x}-\frac{2}{x}\\$$
Ans: x

Answer 4

\[\frac{ 9 }{ x+7 }-\frac{ 2 }{ x }\]

Answer 5

This is as I expected. Please use parentheses to group things. Remember your order of operations.

\(\dfrac{9}{x+7} - \dfrac{2}{x}\) = 9/(x+7) - 2/x

Do you see the difference from what you wrote? It is not a small thing.

Answer 6

thats the question

Answer 7

What't a common denominator. Both denominators are prime, so there are limited choices.

Answer 8

Wouldn't the common denominator just be 7x or something?

Answer 9

Or something. Just x(x+7). There is really no other reasonable choice.

Answer 10

The least common multiple of 1 and x is the common denominator. The 1 is the denominator for the 7 and x is for the others. "x" is the lowest factor between x and 1.

Answer 11

For example, what is the least common multiple between 12 and 18?

Answer 12

What is the smallest positive integer that is a multiple of each?

Answer 13

@ybarrap is still working the problem you originally posted. See how that notation was confusing?!

Answer 14

36. That is the lowest common multiple. And if it were in the denominator, it would be the lowest common denominator.

Answer 15

Okay so I think for the original problem it'd just be x(x+7)

Answer 16

Least common multiple of (x+7,7)? What is it?

Answer 17

Nothing time x+7 gives 7 and nothing times 7 gives x+7, so x(x*7) is the least common multiple (i.e. lowest common denominator)

Answer 18

Okay thank you so much, sorry about the misunderstanding in the beginning.

Answer 19

* (x+7) of course.

Answer 20

right *x(x+7), thanks.