Answer:
y = 98(w) + 115(20 - w).
Explanation:
Ann takes a combine 20 credit hours, and she is taking w credits at Westside, this means that she has to take the rest at Pinewood.
(total credits at Westside)($98) + (total credits at pinewood)($115).
Assuming that she takes all credits at Westside then we say
20(98) + 0, and this is the lowest cost it will be
Assuming she takes all credits at Pinewood, then we say
0 + (20)(115) and this will be the maximum she would pay for 20 credits.
Let y be the total cost of her courses, then we say
y = 98(w) + 115(20 - w).