How do you do this "real world" math problem

A salesperson ears a salary of $700 per month plus 2% of the sales. What must the sales be if the salesperson is to have a monthly income of at least $1800?

I'm so confused on how to do this. Please help! Thank You :)

First I would write an equation to express his income.

(Income) I = 700 + .02S (Sales)
If he wants 1800 in income, plug that in for I and solve for the required Sales.

1800 = 700 + .02S
Subtract 700 from both sides
1100 = .02S
Divide by .02
55000 = S

He needs to make at least $55,000 in sales to earn $1800 monthly.

Hope that helps!

Total salary = base + comission = 700 + x
He wantsd atotal salary of 1800 so 1800 = 700+x
x = 1100
x = comission = 0.02* sales
1100 = 0.02* Sales
Sales = 1100/0.-2 = 55,000 in sales to make a total of 1800