Deandre takes classes at both Westside Community College and Pinewood Community College, At West side , class fees are 98 per credit hour, and at Pinewood, class fees are $115 per credit hour Deandre is taking a combined total of 13 credit hours at the two schools
Suppose that he is taking w credit hours at Westside. Write an expression for the combined total dollar amount he paid for his class fees,
total paid (in dollars)
?

If Bob is taking a combine 18 credit hours, and he is taking w credits at Westside, then he must be taking the rest at Pinewood, what would the expression be for the number of credits at Pinewood?

The expression that represents how much Bob spends for classes at both schools :
(#credits at Westside)($98) + (#credits at pinewood)($115).

If he takes all credits at Westside this is 18(98) + 0, which would be the lowest cost it could be,
if he takes all credits at Pinewood this would be 0 + (18)(115) which would be the maximum Bob could pay for 18 credits.

If y is the total cost of is courses, then
y = 98(w) + 115(18 - w).

Using the distributive property, this can be simplified.