# Combine the two parallel combinations circuits

1. Mar 26, 2007

### Aikenfan

1. The problem statement, all variables and given/known data

2. Relevant equations
V= IR
P = IV

3. The attempt at a solution
Wouldn't you just add 70 and 13 to get 83? if anyone could help it would be greatly appreciated

2. Mar 26, 2007

### Staff: Mentor

There must be more to the question. Do they give you a current and voltage or something? You can certainly combine the top 4 resistors into a total equivalent resisntance, but that does nothing to constrain R itself. What else are you given?

3. Mar 26, 2007

### Aikenfan

I'm sorry, missed that. It says: The equivalent resistance of the circuit in the figure is R eq = 60 ohms: thats all that is given

4. Mar 26, 2007

### SGT

As Berkeman said, combine the 4 known resistors into one equivalent resistor. The combination of this with R is 60 ohms.

5. Mar 26, 2007

### Aikenfan

so it would be 13 + 13 + 70 + 70?
= 166

6. Mar 26, 2007

### Staff: Mentor

No. First combine each series combinatino of 70+13, then combine the two parallel combinations of those to make one top resistor to substitute for the top 4 resistors. Now what does the overall circuit look like? And how then do you solve for R?