# Potential Divider Equation (Rearranging)

1. Nov 15, 2014

### rindishy

• Member warned about use of template.
Hi.

I'm currently learning about potential dividers and need some help with rearranging the formula.

I've managed to rearrange it to make Vin and R1 the subject, but I'm having trouble rearranging for R2.

Can someone help? My maths isn't great, so an explanation would be great. Thanks.

The formula is:

Vout = Vin x R2/(R1 + R2)

2. Nov 15, 2014

### Bystander

What were you wanting from the rearrangement? You've omitted Vout. You can't be trying to eliminate it as a variable.

3. Nov 15, 2014

### rindishy

I want to be able to work out R2. So if for example I had a question where I was given Vout, Vin and R1, but not the value of resistance of R2.

i.e.

R2 =

4. Nov 15, 2014

### Bystander

Okay. Remember you HAVE to treat both sides of an equation the same way, whatever you do to one side, you do to the other; and you want R2 in terms of the other three variables. What's a good place to start? How about multiplying both sides by (R1+R2) and collecting terms containing R2 on one side of the equation? Take a stab at it and I'll be right here online for a while --- football games aren't on yet.