Bill makes leather shoes. he charges $45 for a pair of women's shoes and $50 for a pair of men's shoes. he sells x pairs of women’s shoes and y pairs of men’s shoes each week and earns a total income of $2,500. this situation can be represented by the equation . if bill has no female customers during a particular week, he needs to sell pairs of men’s shoes to earn his weekly income of $2,500. nextreset

$45x +$50y =$2,500
Since you want to know how many men's shoes he must sell to make $2500 , plug 0 in for x pairs of women's shoes.
$45(0) + $50y =$2,500
0 + $50y =$2,500
$50y = $2,500
$50y/50= $2,500/$50
y = 50

He must sell 50 pairs of men's shoes to still earn his weekly income of $2,500

Check

$45(0) + $50(50) = $2,500
$0 + $2500= $2,500
$2500 = $2500

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.