In the attachment is a graph of the cosine function that represents changing of the tide.
y max = 10 ft at midnight
y min = 5 ft at 6 AM
Part A
Your problem statement already shows you the conversion.
Bottles purchased: 5×10¹⁰
Bottles recycled: 8.3×10⁹
Part B
The ratio of bottles purchased to bottles recycled is
... (5×10¹⁰)/(8.3×10⁹) = 0.6×10¹ = 6.0
The number of bottles purchased is 6 times the number of bottles recycle.
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>
She can travel 3000 miles
The one who walked 1.2 miles would have made $72 and the one who walked 0.8 miles would have made $48.
