Superposition to solve circuit with dependent source

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

Assume that Vs = 10V , R1 = 1.7Ω , and R2 = 0.50Ω. Find the current I in the figure using the superposition principle.

2. Relevant equations

Superposition principle
Current and voltage dividers

3. The attempt at a solution

I = I’ + I”

First replacing the current source with an open circuit, I have:

(1.7+0.50)*I’ = 10 – 2I’ using KVL
Solving, I’ = 2.38 A

Now replacing the voltage source with a short, I use the current divider to get:

-I” = 3*0.5/(1.7+0.5) = 0.682 A
I” = -0.682 A

I = 2.38 – 0.682 = 1.7 A, which is incorrect.

EDIT: Should I have left the dependent source as 2I and solved for I in the final equation, or am I doing something else wrong?

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