V = IR

Treat the resistors as if they were one unified value...

I = 8 amps, per your post...

What was the voltage?

Now figure out what your algebra indicates must be the equivalent circuit...

See John's calc's above.^^^

You ought to have Ugly's to hand...

And plainly need to hit the books on first semester algebra.

All electrical problems take these forms.

You might benefit by going to Kahn Academy.

It's free, on the Web, and self-paced.

https://www.khanacademy.org/math/algebraPerhaps a bit too much at first:

http://www.smps.us/references.htmlThis is the diagram that's on the cover of Ugly's:

http://www.sengpielaudio.com/FormulaWheel-ElectricalEngineering.htmI always is used for current ( Unless you're in Physics... then the professor likes to use j.)

R always is used for resistance.

V for voltage is dominant in American usage, E is dominant elsewhere -- again both mean the applied voltage.

For Alternating Current, the voltage always refers to the RMS (Root Mean Square) voltage of the AC waveform.

{ the RMS Voltage x Current in an AC scheme is equal in power to the DC Voltage x Current in a DC scheme. }

Consequently, when these two schemes first met the marketplace, Tesla and Westinghouse pitched the RMS voltage so as to simplfy field calculations -- such as yours.

It was slow going for AC until Tesla published all of the math. Overnight, AC took over long distance distribution. It all came down to the V = IR equation.