X = 0 ; y = 10 ; 10 = a(0) + b(0) + c
c = 10
x=2 ; y = 15 ; 15 = a(4) + b(2) + 10 ; 5 = 4a+2b
x=4 ; y=18 ; 18 = a(16) + b(4) + 10 ; 8 = 16a + 4b
2(5) = (4a+2b)2
-
<u> 8 = 16a + 4b
</u> 2 = -8a
a = -0.25
b = 2
y = (1/4)x^2 + 2x + 10 ; 4y = x^2 + 8x + 40
Answer: 286 minutes
Step-by-step explanation:
x : # of months that has gone by
0.24x : cost of the 24 cent plan after "x" minutes
39.95 + 0.10x : cost of the 10 cent plan after "x" minutes
1. 39.95 + 0.10x > 0.24x
2. 39.95 > 0.24x - 0.10x
3. 39.95 > 0.14x
4. 285.36 > x
x must be AT LEAST 286 minutes for plan #2 (39.95 + 0.10x) to be a better deal
I am assuming there are more than one juice box in a package so if the amount of juice boxes in each package is X and there are four packages 4X.
So 4X - 2= Answer
If we make it so that there are 6 juice boxes in each package and use the same method this is what we'll get:
24 - 2= 22
22 would be the juice boxes left over.
I hope this answers your question, if it doesn't use the same method with the number of juice boxes in a package.
