Cannot apply Complementary Stackness to Dual Linear Problem

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I have the next primal problem.I have to solve It obtaining the Dual problem and up to here everything is nice,but the problem appears when I have to apply the Complementary Slackness:

Primal problem is: Maximize $2x_1+3x_2-4x_3$,
Subject to: ,
$3x_1+5x_2+2x_3=15$ ,
$2x_1+3x_2-4x_3=8$ ,
$x_1\geq0, x_2\geq0,x_3\geq0$

I obtain the Next Dual Problem: Minimize $15\pi_1 +8\pi_2$

Subject to:
$x_1:3\pi_1+2\pi_2\geq2$
$x_2:\ 5\pi_1+3\pi_2\geq3$ ,
$x_3:\ 2\pi_1-4\pi_2\geq-4$

When I solve this dual problem I have that the Dual solution is (0,1).The issue here is when I put it in the equations the condition of $>$ doesnt satisfy,It only satiesfies the condition of =,so I cannot apply Complementary Slackness and say that any primal variable is equal to zero.If anybody knows how to proceed now,I'd very greatful.

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The best way to deal with your problem is to use the strong duality. It says that the the primal optimal objective is equal to the dual optimal objective: $f(x^*)=g(\pi^*)=8$. That means you have three equations with 3 unknowns.

\begin{eqnarray} &2x_1+3x_2-4x_3=&8 \\ & 3x_1+5x_2+2x_3=&15\\ & {2x_1+3x_2-4x_3}=&8\end{eqnarray}

It is obvious that one equation is redundant. So for the optimal solution you have to express two variables by the remaining variable, i.e. $x_1$. And also you have to regard the non-negativity condition. Can you proceed?