A food manufacturer is creating a new snack mix using three types of nuts: almonds, cashews, and walnuts. The table below shows the cost per pound and the grams of protein per pound for each nut.

| Nut | Cost per pound ( $) ∣ P ro t e in p er p o u n d (g) ∣∣ : - - - - - - - ∣ : - - - - - - - - - - - - - - - - - ∣ : - - - - - - - - - - - - - - - - - - - - ∣∣ A l m o n d s ∣5.00∣190∣∣ C a s h e w s ∣7.50∣240∣∣ Wa l n u t s ∣6.00∣310∣ T h eco m p an y w an t s t h es na c kmi x t o ha v e a t o t a lw e i g h t o f 50 p o u n d s . I f 12 p o u n d so f c a s h e w s a re u se d, w hi c h o f t h e f o ll o w in g e q u a t i o n sco u l d s h o wt h ere l a t i o n s hi p b e tw ee n t h e am o u n t s,$ x $an d$ y $, in p o u n d s, f ore a c h o f t h eo t h er n u tt y p es u se d ?$