Question

Turn equation into a function of y.
y = 6x - 2x^2
I came up with (sqrt(9-2y) -3)/2, but when I saw it graphed, the portion of the graph I'm trying to get, wasn't correct....

Answer 1

Its a parobola

Answer 2

So u need to find the vertex at first

Answer 3

Or use baskara

Answer 4

Read my answer here: http://openstudy.com/study#/updates/50525a77e4b0d48070306859

Answer 5

Did I phrase it wrong? I want an equation as a function of y, not the possibilities of what x could be...

Answer 6

Ok, I don't think I understood the question

Answer 7

You want x as a function of y?

Answer 8

I want the equation a function of y, instead of x..... so turned into x = [insert rewritten equation here]

Answer 9

Yes, thats what I though, you can still do what I said, look at the last post in that page, you only need to put y instead of 0, and I just saw a mistake there, after summing b^2 it should be on both sides.

Answer 10

Yeah, I have put y instead of zero.... that's kind of how you go about solving for a different variable. It's just not working out well because my algebra from high school was taught very poorly, and like my fellow classmates I barely managed to scrape by.

Answer 11

it is not a one to one function, so it will not be a function of \(y\)

Answer 12

Gahhhhh, then I'm not sure how turn it into a cylindrical shell for volume..... guess I'll try it as a function of x and see if it comes out right or not....

Answer 13

also i think i see a mistake. i think the \(-3\) in your answer should be a 3

Answer 14

maybe i am wrong, let me see
\[y = 6x - 2x^2\]
\[2x^2-6x+y=0\]
\[x=\frac{6\pm\sqrt{36-8y}}{4}=\frac{3\pm\sqrt{9-2y}}{2}\]