A levels physics- electricity question (4)

Seems like Power would be Intensity times Area times Efficiency...
P=IAE
and you need to rearrange to make A the subject

Intensity is given in Watts / m^2
So intensity multiplied by area is the input power.
Efficiency is the proportion of input power that ends up as output power.

Thank you for explaining, I finally understand! But just double checking for Intensity= input power/ Area , is it always Input power and never output used ? If so why input as idk intuitively I would think the intensity would be to do with the output power because ( sorry for this silly example it’s all I can think ) for example the intensity of the a light we see shining I would think the intensity we saw would depend on the output?

I think they're assuming some common knowledge about what solar panels do... I. E. Solar panels take in light as input and produce electricity as their useful output.
Solar panels produce quite a lot of waste heat so they have quite a low efficiency... But since sunlight is basically free it's usually not considered a serious problem.

thank you so much that makes sense! also why does input power= intensity x area of solar cell is it just a formula everyone must knows or did you use logic to come up with it ? ( sorry for asking so many follow up questions I just find it easier to remember it in exams when I fully get it)