Single equation with 2 unknowns

[KateO]

hiya, if i have the equation:
y=0.2sin(5x-1100t)
and i need what t = when y - 0.1

how do i do this without knowing x / how do i find x?
thanks u
- kait

 

[lightgrav]

You can't solve a single equation with 2 unknowns.
The x-value to use is hidden in the wording of the problem scenario ...
... probably the origin , x= 0 .

OR,
they want the time for a piece of string to go from y = .2 (say)
to y = -.01 , which means you get to choose your x - location.

 

[KateO]

would finding the wavelength not help at all? is x the wavelength??
or no...