Lagrange multiplier with first order variables

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Quite a trivial question but it's bugged me. The problem I have to optimize is:

maximalise: $3x + 2y$

subject to:

$x + 3y \leq 17 $

$2x + y \leq 10 $

$x \leq 2$

$x, y > 0 $

I started to use the Lagrange multiplier with $λ_1$ and $λ_2$ for the first two constraints, but I realized that, as the $x$ and $y$ used are first order variables, the partial differentiation only gives me a system of two equations with $λ_1$ and $λ_2$, and no $x$ and $y$. That way, I can only find $λ_1$ and $λ_2$, but not $x$ and $y$.

So, could I use the Lagrange multiplier in some way so as to find the optimal solution? Or should it be done in another way?

Thanks for your time.