Question

it also shows the buying and selling arrangements for galaxium among the planets.
planet | buys galaxium from | sells galaxium to
alir | alir, lamy, tixo | all eight planets
bilk | alir, bilk, piaf | alir, bilk, tixo
jas | alir, jas, plaf, sydow | jas, tixo
lamy | alir, jas, lamy, piaf | alir, lamy, tixo
piaf | alir, plaf | bilk, lamy, piaf, tixo
sydow | alir, sydow, tixo | jas, sydow, tixo
tixo | all eight planets | alir, sydow, tixo, wil
wil | alir, tixo, wil | tixo, wil
your answer
let ( u ) be the set of all eight planets.
( u = { \text{alir}, \text{bilk}, \text{jas}, \text{lamy}, \text{piaf}, \text{sydow}, \text{tixo}, \text{wil} } )
let ( x ) be the set of planets bilk buys galaxium from.
let ( y ) be the set of planets tixo does not sell galaxium to.
find the sets below. write each answer in roster form or as ( varnothing ).
(a) ( x = { \text{jas}, \text{lamy}, \text{sydow}, \text{tixo}, \text{wil} } )
(b) ( y = square )

Explanation:

Step1: Identify set Y's complement

From the table, Tixo sells to {Alir, Sydow, Tixo, Wil}. $Y'$ is planets Tixo does NOT sell to.
$Y' = U - \{\text{Alir, Sydow, Tixo, Wil}\}$

Step2: Calculate set Y

$Y$ is the complement of $Y'$, so $Y = \{\text{Alir, Sydow, Tixo, Wil}\}$

Answer:

$\{\text{Alir, Sydow, Tixo, Wil}\}$