Answer:
18 bottles of water for $10 because each bottle costs 56c compared to 6 bottles of water for $4 at 67c
Step-by-step explanation:
All values rounded to the hundredth
6 bottles of water for $4
4/6=0.67
Each bottle costs 67c
18 bottles of water for $10
10/18=0.56
Each bottle costs 56c
Let Xavier's favourite fraction be a/b, Yessie's favourite fraction = b/a and Zorro's favourite fraction = c/d,
c/d x a/b = 12/35 . . . . . . . . (1)
c/d x b/a = 15/7 . . . . . . . . (2)
(1) x (2) = c/d x a/b x c/d x b/a = 12/35 x 15/7
c^2 / d^2 = 36/49
c^2 = 36
c = 6
d^2 = 49
d = 7
Xaviers favourite fraction = 12/35 / 6/7 = 2/5
Yessies favourite fraction = 5/2
Zorro favourite fraction = 6/7
Let u = x², then we would have u² + 5u - 6 = 0
From here, we can factor it and get us (u-1)(u+6) = 0
So our solution for u is u = -6 or 1.
Now substitute u back to x².
x² = -6 or 1
x = ±√(-6) or ±√1
Since ±√(-6) is not real number, we ignore it.
Which leave us x = ±√1 = <span>±1
So our real solution is x = -1 or 1.</span>
