Michael is running a concession stand with his friends at a high school football game. Michael is told to sell the hamburgers and sodas. Each hamburger costs $3.50 and each soda costs $1.50. At the end of the night Michael made a total of $108.50. Michael sold a total of 78 hamburgers and sodas combined. He must report the number of hamburgers and sodas sold to his teacher. How many hamburgers were sold and how many sodas were sold?

Hamburgers cost $3.50
Sodas cost $1.50
Made a total of $108.50
Sold 78 hamburgers and sodas combined
Let x = number of hamburgers sold

Let y = number of sodas sold

3.50x + 1.50y = 108.50 (Equation related to cost)

x + y = 78 (Equation related to the number sold)