Why did the math teacher open a window company

Ineed to learn how to solve this problem

Which ahows the graph of the solution set of 6x+4y< 12

Draw a tape diagram to represent each situation.for some of the situations,you need to decide what to represent with a variable andre bakes 9 pans of brownies.he donates 7 pans to the school bake sale and keeps the rest to divide equally among his class of 30 students