1. if a medium pizza costs $5 and a large pizza is $8 write an equation in standard from that models the possible combinations if you have $40 (let m=medium , l=large).
2. if you brought only medium pizzas in problem 1 then how many could you purchase?
3.if you brought 4 medium pizzas in problem 1 , how many large pizzas could you purchase?
Now, these would follow a different form of an equation of a line. The form is Ax + By = C. C here would be the total money you have, 40. A and B would be the cost of the pizzas, 5 and 8. Now, here, though, x and y would change to m and L. So, we would have 5m+8L = 40. It has to be 5m and 8L, since 5 is the cost for a medium and L is the cost for a large.
For #2, "only mediums" would mean L = 0. So, 5m+8*0 = 40. Or, 5m+0 = 40. Or, 5m = 40. Or, m = 8.
For #3, if m = 4, then we would have 5*4+8L = 40. So, 20+8L = 40. Subtract 20 from each side, 8L = 20. Divide by 8, L = 20/8 = 2.5. So, you could get 2.5 large pizzas. Now, this could be a question where you can't get half of a pizza. So, then, you would round this down, where you would only be able to buy 2 entire large pizzas.
Good luck, quddoos. I hope this helps.