Wave-Particle Duality and Equations Used

[Junghyuk_Park_1I]

I'm a bit confused on the Wave-Particle Duality of light. So light behaves both as a wave AND particle (photon), and we don't know how to properly draw out a beam of light correct? In terms of the equations, my question is the following:
So if equations such as c=(wavelength)*(frequency) describe light as a wave while equations such as E = h*(frequency) describe light as a photon particle, is it okay to use them in the same problem involving light calculations even though they are describing light differently? Is the duality of light thought of more as two different ways to describe light that work together or as two separate descriptions entirely? Or do I have this wrong in any way? Thanks in advance.

[Aaron_Trell_2J]

Both of the equations that you mentioned can be used in the same problem (assuming you are talking about the photoelectric effect). For example if the problem asks you to calculate the energy of the light source and you are given the frequency you can simply use the equation E=h x (frequency). However if they give you a wavelength then you have to substitute c/(wavelength) in for the frequency and this substitution is derived from the equation c= (frequency)x(wavelength). As for the difference between the two models of light, these models were only brought about due to experimental results that were obtained and are typically not used together. Hope this helps.