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## Homework Statement

Determine the voltage across ##R_3## in the following figure assuming an input voltage ##v_0## of 10V is applied across the open terminals.

Let ##R_1=3\Omega##, ##R_2=15\Omega##, ##R_3=10\Omega##, ##R_4=5\Omega## and ##R_5=2\Omega## and

## Homework Equations

## The Attempt at a Solution

So I'm trying to use Thevenin's theorem to solve this, I already solved it using basic current/voltage rules and I obtained ##V_{R3}=4V##, if I set ##R_3## as the load resistor I obtain the following circuit:

Now I can't see how to find ##R_{th}## by shorting the voltage source and then combining the resistors, I believe I can just remove ##R_4## in that scenario but then I have ##R_1##, ##R_2## and ##R_3## connected together and I'm not sure which of these two are in parallel (if someone could explain how to go about solving it this way that would be great). Because of this I decided to find ##R_{th}## using ##V_{th}## and the open circuit current, if I short ##R_3## then we have ##R_2##//##R_4## so by a voltage divider we obtain ##I_{sc}=\frac{v_0}{R_1+\frac{R_2R_4}{R_2+R_4}+R_5}##. Now to find the voltage ##V_{th}## we need the voltage across ##R_3##, I would've thought that it would just be ##V_{th}=\frac{V_0}{R_1+R_2+R_5}R_2##. However, this doesn't lead to the correct answer after calculating ##R_{th}## using ##V_{th}=I_{sc}R_{th}## and then building the thevenin equivalent circuit.