Trying to figure out the missing resistor in a parallel circut

R1= 20
R2=?
Rt= 13.33

Any help would be great

 

Welcome to AAC!

In homework help, you need to show your best effort so we can see where you're having difficulty.

 

Write out the equation for parallel resistance. Then, manipulate the equation to isolate R2.

 

Write out the equation for parallel resistance. Then, manipulate the equation to isolate R2.

Thanks. Was trying to figure out the equation

 

It's just simple algebra. Practice it until you can do it in your sleep.

 

Was trying to figure out the equation

For calculating the resistance of two resistors in parallel?

 

Thanks. Was trying to figure out the equation

So show your work. Maybe we can help. What is your starting point? If you have known values for R1 and R2, how would you calculate Rt? Start with that formula.

Also, see if you can place some limits on what the value of R2 can be? What would Rt be if R2 was 20 Ω? Based on that, does R2 need to be more or less than 20 Ω. This will help you catch wrong answers instead of just blindly accepting them.

 

It goes something like this: