Kevin takes classes at both Westside college and Pinewood college at Westside class fees are $98 per credit hour and Pinewood they are $115 per credit hour. Karen is taking combined total of 18 credit hours at the two schools. Suppose that she's taking W credit hours at Westside. Write an expression for the combined total dollar amount that she paid for the class fees​

y = 98(w) + 115(18 - w)

Step-by-step explanation:

The expression that represents how much Kevin 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.