I know this is really a math question but I'm using Excel to solve.
I pulled trendline polynomial equations from the enclosed chart and set them equal to each other to see where they cross.
0.1333x^2 - 5.333x + 65 = 0.0333 x^2 - 2.667x + 70
Then used the quadratic equation to solve for x but I am getting a value of 0.28 when I would expect a value closer to 30 from the graph. What am I doing wrong?
ChemistB
My 2?
substitute commas with semi-colons if your region settings requires
Don't forget to mark threads as "Solved" (Edit First post>Advanced>Change Prefix)
If I helped, Don't forget to add to my reputation (click on the little star at bottom of this post)
Forum Rules: How to use code tags, mark a thread solved, and keep yourself out of trouble
Those two parabolas cross twice, right?
If you have
ax^2 + bx + c = dx^2 +ex + f
... the result is a single quadratic that you can solve for (in this case) two real roots in the usual way?
Last edited by shg; 05-23-2014 at 01:00 PM.
Entia non sunt multiplicanda sine necessitate
Hi Chemist,
You just need your denominator in brackets:
(2*P17)
Regards
Doh !
Sigh, it must be Friday. Thanks XOR
Aye! I'll drink to that!Originally Posted by ChemistB
Hey SHG! No comments from the peanut gallery. LOL
@CB: The Doh was self-directed ...
In my defense, I would point out that the other crossing is at -1.76
You can aim that doh at me also. I certainly deserved it.
There are currently 1 users browsing this thread. (0 members and 1 guests)
Posting Permissions
LinkBack URL
About LinkBacks
Register To Reply
Bookmarks