Thevenin Resistance Problem

Hi, Can anybody please tell me how to find the Thevenin Resistance in this circuit.. Thank you!

http://img832.imageshack.us/i/theveninpr…

It is not 16.67 sorry,

Replace the source with the ideal internal resistance (voltage source) = a short(wire)
k look at it from points A and B, youll have a 10 ohm in parallel with a series parallel circuit
the the two 10 ohm resistors in parallel turn into 5 ohms
and the 5 ohms is in series with a 10 ohm so the overall circuit turns into 15 Ohms || 10 Ohms

6 Ohms is the Thevenin resistance, the thevenin voltage is the voltage accross the 10 Ohm resistor on A and B so first find the total resistance thats 16.667 Ohms= 10 Ohms + 10||20

then use the voltage divider equation to find the voltage accross the parallel part of the circuit
10*(6.67/16.67) =4 Volts now to get the voltage accross the Points A and B use another voltage divider equation and you get 4*10/20 = 2 Volts as your Thevenin Voltage

Rth = 10 + 10//10 = 10 + 5 = 15 ohms

Vth = (10/15)10 = 6.667 volts