Question

I am trying to model a cubic graph:
I want it to pass through the origin, x=60 and x=120. So far I have:
y=kx(x-60)(x-120).
i also want it to have a point (30,12). I tried to find a k value (1/4500) but it is not giving me the point i wanted?! help plz!!

Answer 1

so the cubic goes through
(30,12)?
if so replace y with 12
and x with 30
and solve for k

Answer 2

or is that what you did?

Answer 3

Try solving one more time...you should be getting a different k value

Answer 4

omg i cant subtract

Answer 5

lol

Answer 6

so you got it now?
it is easy to screw up the arithmetic :p

Answer 7

Yes thanks!