What is -6 x -4 ?

sorry i suck at math

What is the slope of the line shown below?

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.

Yo need asap pls ! markin da brainiest too !