Ask your own question, for FREE!
Mathematics 15 Online
OpenStudy (anonymous):

questio

OpenStudy (rainbow_dash):

answer.

OpenStudy (anonymous):

\[\frac{ 3x }{ x+2 }+1=\frac{ -6 }{ x+2 }\]

OpenStudy (australopithecus):

\[\frac{3x}{x+2} + \frac{x+2}{x+2} = \frac{-6}{x+2}\] can you solve it now?

OpenStudy (anonymous):

no i dont get how to

OpenStudy (anonymous):

Adding fractions with common denominators?

OpenStudy (australopithecus):

can you at least simplify it?

OpenStudy (australopithecus):

how far are you getting?

OpenStudy (anonymous):

i get \[3x^{2}+2\]

OpenStudy (anonymous):

=?

OpenStudy (anonymous):

Don't lose the equals sign if it's an equation.

OpenStudy (anonymous):

-6

OpenStudy (anonymous):

Ok, you have a nice mild quadratic equation there to solve.

OpenStudy (anonymous):

Note that what's important here, is now that all the denominators are equal, then the numerators must be equal. You'll have the restricted domain of x =/= -2 as well, so watch out for that.

OpenStudy (anonymous):

so \[3x^{2}+2+6=0\]

OpenStudy (anonymous):

Oh, hold up...

OpenStudy (australopithecus):

wait how did you get a quadratic

OpenStudy (anonymous):

Bah, it's just addition. I think I had my eyes crossed there.

OpenStudy (australopithecus):

you shouldn't get a quadratic for this problem

OpenStudy (australopithecus):

I'm just going to show you the simplification steps

OpenStudy (australopithecus):

please take the time to understand them

OpenStudy (australopithecus):

if you have any questions ask

OpenStudy (anonymous):

I have a question: Aren't those more steps than are necessary?

OpenStudy (anonymous):

how do you get 6x

OpenStudy (australopithecus):

it was a mistake

OpenStudy (anonymous):

From \[\large \frac{3x}{x+2}+\frac{x+2}{x+2}=\frac{-6}{x+2}\] \[\large \rightarrow 3x+x+2=-6, x \ne-2\]

OpenStudy (australopithecus):

\[\frac{3x + x + 2}{x+2} + \frac{6}{x+2} = \frac{-6}{x+2} + \frac{6}{x+2}\] \[\frac{3x + x + 2}{x+2} + \frac{6}{x+2} =0\] \[\frac{3x + x + 2 + 6}{x+2} =0\]

OpenStudy (australopithecus):

now you can eliminate the denominator and solve very easily

OpenStudy (anonymous):

how does x=-2

OpenStudy (anonymous):

\[\large \rightarrow 4x=-8, x\ne-2\] Therefore no solution?

OpenStudy (australopithecus):

cliffsedge I think you should be more descriptive why x=/= 2 yes x = -2 is the solution you get but remember you cannot have a denominator of 0, what makes the denominator 0 in this equation?

OpenStudy (australopithecus):

i mean x =/= -2

OpenStudy (anonymous):

^ @Australopithecus , yes, good point. I mentioned 'restricted domain' and had assumed that rachalh had already covered that concept elsewhere.

OpenStudy (anonymous):

Another way of seeing it is to write it as a function \[\large y=\frac{3x+x+2+6}{x+2} = \frac{4(x+2)}{x+2} \] \[\large \rightarrow y=4, x\ne-2\] And graph it and see that it is a horizontal line that will never cross the x-axis.

OpenStudy (anonymous):

thank you

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!