x represents the number of packages of coffee sold
y represents the number of packages of pastry sold
We were the cost of a package of coffee is $6 and the cost of a package of pastry is $4. If the total amount made from selling x packages of coffee and y packages of pastry is $72, then the equation representing this scenario is
6x + 4y = 72
Also, we were told that she sold 2 more packages of coffee than pastries. This means that
x = y + 2
Thus, the system of linear equations is
6x + 4y = 72
x = y + 2
We would plot these equations on the graph. The graph is shown below
The red line represents x = y + 2
The bu line represents x = y + 2