## Math2400 one year ago can someone help me solve this (easy but haven't done it in a while)

1. xcharlizea

sure thing boo thangg

2. Math2400

$0.27 = \frac{ 110^2 }{ (y-111)^2 (y-55) }$

3. xcharlizea

o wtf

4. xcharlizea

lmaoo hold up gimme a min

5. zepdrix

What are we doin? +_+ solvin for y?

6. Math2400

yes haha

7. zepdrix

Multiply and divide some things,$\Large\rm (y-111)^2 (y-55)= \frac{ 110^2 }{0.27 }$Then I guess expand out all those brackets.

8. zepdrix

Then you get a cubic.... which.... might be hard to solve :d hmm

9. Math2400

wait it's supposed to be (y-110)^2 lol not 111/ but how do u do a cubic? LOL

10. zepdrix

$\Large\rm (y-110)^2 (y-55)= \frac{ 110^2 }{0.27 }$Well you know how you have your nice quadratic formula for dealing with squares? x= -b+/-sqrt(b^2-.... Well there is one for cubics, but it's extremely long and complex, not worth using most of the time. We could try applying rational root theorem to find a factor, and then factor it. If it doesn't factor, then..... oh boy +_+

11. Math2400

what is the equation for cubic? lol i think my professor wants us to know

12. zepdrix

i doubt it :) lol http://www.math.vanderbilt.edu/~schectex/courses/cubic/

13. zepdrix

it's the formula that's taking up two lines

14. zepdrix

near the top

15. zepdrix

or you could just cheat and use wolfram +_+ https://www.wolframalpha.com/input/?i=%28y-110%29%5E2%28y-55%29%3D110%5E2%2F0.27

16. zepdrix

it's a weird solution.. not one we could've come up with just by checking roots and stuff :d

17. zepdrix

There is probably some calculus techniques you could use to get really close to the solution... blah