Answer:
C for the first problem
D for the second One
Step-by-step explanation:
First One
This problem is a monster. There are so many letters flying around that you hardly know what is going on. I'll try and break it down a little at a time.
Width of the car = x
radius of the car = y
The width of the car must be at least 2 inches greater than radius
x ≥ y + 2 or
x - 2 ≥ y or
y ≤ x - 2
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Area: L * w
Area of the base = x*(x + 3)
Cost of Area = x*(x + 3)*0.5
Cost of Area = (x^2 + 3x)*0.5
Cost of Area = 1/2 x^2 + 1.5x We'll add fractions later.
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The radius = y which is more commonly
For every inch of the radius, there is a cost of 2.25
For every inch of the radius, the cost = 2.25 * y
There are 4 wheels which cost 2.25*4*y= 9y
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Total cost 9y + 1/2x^2 + 1.5x ≤ 50
Now here's where the problem get's really hairy. You have to solve for y
9y ≤ 50 - 1/2x^2 - 1.5x 50 dollars - base still has to be <em><u>more than </u></em> 9y
Now divide by 9. This too can be a little ugly.
9y / 9 ≤ 50 - (1/2 // 9/1) x^2 - 1.5/9 x
y ≤ 50/9 - 1/2 * 1/9*x^2 - 1/6 x
y ≤ 50/9 - 1/18 x^2 - 1/6 x
I'll leave you to find the correct letter.
Second Problem
The real snake in this problem is the 22 dollars. What to do with it. It says flat rate and I interpret that to mean there is no x with it. That eliminates B.
I think the only equation you can use is
C(x) = (15x + 22) / x All the people there have to share in paying the 22 dollars is what that statement means.
The answer is D