Answer: he has to sell 42 seat covers.
Explanation:
Let x represent the number of seat covers that Jacob makes and sells.
He invested $120 for marketing purposes. His rent is $750. He spends $7 for raw materials for each seat cover he makes. This means that the total amount he would spend in making x seat covers is
120 + 750 + 7x
Jacob can sell the seat covers for $28 each. This means that the total revenue that he would generate from selling x seat covers is 28x.
The number of seat covers he needs to sell to cover his expenditure would be
28x = 120 + 750 + 7x
28x - 7x = 870
21x = 870
x = 870/21
x = 41.4
The number of seat covers must be a whole number and if he sells 41, it wont be enough. Therefore, he has to sell 42 seat covers