Austin and his children went into a restaurant where they sell drinks for $1.50 each and tacos for $3 each. Austin has $30 to spend and must buy at least 15 drinks and
tacos altogether. Also, he must buy a maximum of 15 drinks. If x represents the
number of drinks purchased and y represents the number of tacos purchased, write
and solve a system of inequalities graphically and determine one possible solution.