Hi, I am having a bit of trouble solving for an unknown current. Can anyone help me out, thanks.(adsbygoogle = window.adsbygoogle || []).push({});

The resistor R in Fig18.56 dissipates 11 W of power. Determine 2 possible values of R (V= 76 V).

My attempt so far,

1st loop: 35I-35I1=76

2nd loop: I=[(70/30)+(R/30)]I1

I plugged equation (2) into (1): 81.667I1 +1.1667I1R-35I1

=76...(3)

Given that:

I1R =11W/I1

plug that into (3): 46.667I1 +12.8337/I1 -76=0

I've tried using quadratic equation to solve for I1, then plugging into P=I^2R to solve for R, but I still keep getting the wrong answer. Please help. Thank you.

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# Homework Help: Resistors problem. please help, thanks!

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