s = total sales
$45,000 is his goal
$13,000 is his base salary
Luca gets 4% commission on his sales. 1.04s = total sales + 4% commission on sales
base salary + (total sales + 4% commission) = 45,000
AKA
13,000 + 1.04s = 45,000 --> Subtract 13,000 from both sides
1.04s = 32,000 --> Divide both sides by 1.04 to find the total sales
s = $30769.24 (2.d.p.)
