Are you allowed to also use the relationship that P=IV? Because given that equation, it is then just a matter of simple replacement. V=IR (Ohm’s law), so replace the V in the first equation with IR to get P=I^2R.

@Mariah, you are absolutely correct!

I learned Ohm’s law many years ago using “E” instead of “V”. P=IE and E=IR, therefore P=I(IR)=I^2R

Thank you!