Is 3,564 a prime number

At the county fair, the baxter family bought 6 hot dogs and 4 juice drinks for $12.90. the farley family bought 3 hot dogs and 4 juice drinks for $8.55. find the price of a hot dog and the price of a juice drink.

Ineed here’s a picture of the question

Find the vertex for the parabola given by the function ƒ(x) = −3x2 − 6x.