Wyatt runs a farm stand that sells blueberries and raspberries. Each pound of
blueberries sells for $1.50 and each pound of raspberries sells for $3. Wyatt sold 12
more pounds of blueberries than pounds of raspberries and made $72 altogether.
Graphically solve a system of equations in order to determine the number of pounds
of blueberries sold, x, and the number of pounds of raspberries sold, y.