DeAnn is running a lemonade stand at festivals all summer. She sells cold lemonade for $2 / cup and lemonade slushies for $4/ cup. A festival costs her $50 for a vendor license and her supply costs are
$0.30 / cup for lemonade and $0.50 / cup for the slushies. DeAnn wants to make a profit of more
than $200 but she only has $90 to spend on costs ahead of time. Create a total profit and a cost
equation to model the situation with x = # of cups of lemonade and y = # of cups of slushies