anonymous 5 years ago how do you solve 6x-10 over 7 divided by 9x-15 over 21?

1. anonymous

Well without it being equal to something you can't really 'solve' it...

2. anonymous

no there's a way to solve it because someone got the answer but i dont know what it is

3. amistre64

it can be reduced, simplified; but not really solved; its always gonna have an x in it unless that x factors out

4. anonymous

so what would the answer be and how would you get that answer?

5. amistre64

the other option is to plot the points on a graph that result from inputing values of x and the graph becomes the solution.... but without knowing tha tthis is a function with respect to x its rather redundant

6. anonymous

Is this the expression? $(6x-10) \div {{9x - 15} \over 21}$

7. anonymous

no.. 6x - 10 is over 7, but everything else is right

8. anonymous

${{6x-10} \over 7}\div {{9x - 15} \over 21}$$=2({{3x-5} \over 7}) \div 3({{3x-5} \over 7})$$={{2({{3x-5} \over 7})} \over {3({{3x-5} \over 7})}}$$= {2 \over 3}$

9. anonymous

Though you do need to stipulate that x cannot be equal to 5/3.

10. anonymous

one question.. how did you get both denominators 7?

11. anonymous

oh wait. I'm wrong.

12. anonymous

${{6x-10} \over 7}\div {{9x - 15} \over 21}$$=2({{3x-5} \over 7}) \div {3 \over 3}({{3x-5} \over 7})$$={{2({{3x-5} \over 7})} \over {1({{3x-5} \over 7})}} = 2,\ \forall x \ne {5 \over 3}$

13. anonymous

Forgot I factored a 3 from the top and bottom of the fraction on the right.

14. anonymous

thx .can you help me with another problem?

15. anonymous

maybe

16. anonymous

Heres the problem...8-y over y squared + 4 minus y - 2 over y squared + 4

17. anonymous

It would be very helpful if you would write these up in the equation editor because there are a number of ways to interpret what you wrote there.

18. anonymous

oh i didn't know you could do that. because I'm kind of new to this website ....... 8-y/y squared + 4 minus y-2/y squared + 4? does that make a little more sense because I don't know how to do exponents so I just wrote it out

19. anonymous

${{8-y} \over y^2+ 4} - {{y-2} \over y^2+ 4}$ That?

20. anonymous

yah. how did u do that but anyway how do u solve it??

21. anonymous

Well they are over a common denominator already so just subtract the numerators.

22. anonymous