Looking for speed using the wave equation

[Ashley1nOnly]

Homework Statement

phi(x,t) = A e *[-a(bx+ct)*2]
I'm trying to find the speed of the equation

Homework Equations

f(x+vt) +vt which means it is in the negative x-direction
f(x)= e^-ax^2
plugging in x'=x+vt
A e *[-a(bx+ct)*2]
where a= constant A= amplitude v=c= speed of light

The Attempt at a Solution

I know that is speed = w(angular frequency)/K
This issue that I am having is that I don't have any number besides c which is the speed of light
I know that I can use partial fractions [partial phi/ partial t]divided by [partial phi/ partial x] but I'm not allowed to use that way. What is another way I can solve this problem

 

[Ashley1nOnly]

V=W/K
V=B/A
SINCE IT IS GOING IN THE -X DIRECTION

 

[rude man]

ANY function f(x + vt) is a wave traveling in the -x direction with speed v.
Consider: at t=x=0 the function is max = A. For t>0 what values of x maintain the value f=A?