latex的约束问题排版

egin{subequations}label{eq:ctr_shale}
egin{align}
min  sum_{j, k} r_{k} n_{k} frac{V_{j}}{	heta_{j}}left(x_{k j} -	heta_{j}
ight)^{2} +sum_{j} p_{j} u_{j} - lambda sum_{j, k} r_{k} n_{k} x_{k j} c_{k j}    	ag{
ef{eq:ctr_shale}}
end{align} 
egin{alignat}{2}
	ext{s.t.} & sum_{k in Gamma(j)} r_{k} n_{k} x_{k j}+u_{j}  geq d_{j}, forall j  &	ext{ (demand constraints)}   \
    &sum_{j in Gamma(k)} x_{k j} leq 1,  forall k & 	ext{(supply constraints)}  \
    &r_{k} x_{k j} leq f_{j},  forall k,j &	ext{ (frequency constraints)} \
    &n_{k} x_{k j}  leq 1,  forall k, j  &	ext{ (slot constraints)}      \
    &  x_{k j}, u_jge 0,   forall k, j  &	ext{ (non-negativity constraint)} 
end{alignat}
end{subequations}