differential equations - Convert DE to first order?

I have the following set of second-order differential equations:

eqs = {Derivative[2][x][t] + 
     l0 Sin[ϕ[
        t]] (Sin[θ[t]] (Derivative[1][θ][t]^2 + 

           Derivative[1][ϕ][t]^2) - 
        Cos[θ[t]] Derivative[2][θ][t]) - 
     l0 Cos[ϕ[
        t]] (2 Cos[θ[t]] Derivative[1][θ][
          t] Derivative[1][ϕ][t] + 
        Sin[θ[t]] Derivative[2][ϕ][t]) == 0, 
   Derivative[2][y][t] + 
     l0 Cos[θ[
        t]] (-2 Sin[ϕ[t]] Derivative[1][θ][
          t] Derivative[1][ϕ][t] + 

        Cos[ϕ[t]] Derivative[2][θ][t]) - 
     l0 Sin[θ[
        t]] (Cos[ϕ[t]] (Derivative[1][θ][t]^2 + 
           Derivative[1][ϕ][t]^2) + 
        Sin[ϕ[t]] Derivative[2][ϕ][t]) == 0, 
   l0 Cos[θ[t]] Derivative[1][θ][t]^2 + 
     Derivative[2][z][t] + 
     l0 Sin[θ[t]] Derivative[2][θ][t] == 0, 
   l0 (-g m Cos[θ[t]] - 
       l0 Cos[θ[t]] Sin[θ[t]] Derivative[1][ϕ][

          t]^2 + Cos[θ[
          t]] (-Sin[ϕ[t]] Derivative[2][x][t] + 
          Cos[ϕ[t]] Derivative[2][y][t]) + 
       Sin[θ[t]] Derivative[2][z][t] + 
       l0 Derivative[2][θ][t]) == 0, 
   l0 Sin[θ[
       t]] (2 l0 Cos[θ[t]] Derivative[1][θ][
         t] Derivative[1][ϕ][t] - 
       Cos[ϕ[t]] Derivative[2][x][t] - 
       Sin[ϕ[t]] Derivative[2][y][t] + 

       l0 Sin[θ[t]] Derivative[2][ϕ][t]) == 0};

How do I convert them into state-space form, i.e. first order differential equations? Documentation on state-space didn't help. Thanks!

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