A food truck sells 3 menu items; a tortilla wrap for 4.5$, a sub for 7.5$, and a cheeseburger for 6$. Friday they sold a total of 124 items and took in 780$. They sold ten less subs than tortillas and cheeseburgers combined.

1. Give the equation that results from the number of subs sold compared to the number of cheeseburgers and tortillas.
2. Give the equation that results from the total number of items sold
3. give the equation that results from the money collected
4. give the above systems of equations in matrix form