Answer:
I will try to help you. I'll tap in once I figure it out. :)
y = x³ + 3x² - x - 3
0 = x³ + 3x² - x - 3
0 = x²(x) + x²(3) - 1(x) - 1(3)
0 = x²(x + 3) - 1(x + 3)
0 = (x² - 1)(x + 3)
0 = (x² + x - x - 1)(x + 3)
0 = (x(x) + x(1) - 1(x) - 1(1))(x + 3)
0 = (x(x + 1) - 1(x + 1))(x + 3)
0 = (x - 1)(x + 1)(x + 3)
0 = x - 1 or 0 = x + 1 or 0 = x + 3
+ 1 + 1 - 1 - 1 - 3 - 3
1 = x or -1 = x or -3 = x
Solution Set: {-3, -1, 1}
81 servings. I found this by making a ratio:
24 c 108 c
------- = -------
18 ser x
I then cross multiplied to get the equation: 24x=1,944. I solved this equation to find x, the number of servings in 108 cups, which was 81.
I remember doing this back in elementary school. I had a hard time with it too!