1 muffin = 1/4 cup
2 muffins = 1/2 cup
3 muffins = 3/4 cup
4 muffins = 1 cup
5 muffins = 1 and 1/4 cup
6 muffins = 1 and 1/2 cup
9x^2 - 8x - 1 = 0
(9x + 1(x - 1) = 0
x = -1/9 , 1
x intercepts are -1/9 and 1.
Here is the inequality you can enumerate:
5x >= 200, this means the money you sold for cakes must be larger or equal to your goal
x <= 100, this means you cannot sell more than 100 cakes, because you only have 100 cakes
Solve for them, you will get: 40 <= x <= 100
