General Idea:
Domain of a function means the values of x which will give a DEFINED output for the function.
Applying the concept:
Given that the x represent the time in seconds, f(x) represent the height of food packet.
Time cannot be a negative value, so
The height of the food packet cannot be a negative value, so
We need to replace 
for f(x) in the above inequality to find the domain.
![-15x^2+6000\geq 0 \; \; [Divide \; by\; -15\; on\; both\; sides]\\ \\ \frac{-15x^2}{-15} +\frac{6000}{-15} \leq \frac{0}{-15} \\ \\ x^2-400\leq 0\;[Factoring\;on\;left\;side]\\ \\ (x+200)(x-200)\leq 0](https://tex.z-dn.net/?f=%20-15x%5E2%2B6000%5Cgeq%200%20%5C%3B%20%5C%3B%20%20%5BDivide%20%5C%3B%20by%5C%3B%20-15%5C%3B%20on%5C%3B%20both%5C%3B%20sides%5D%5C%5C%20%5C%5C%20%5Cfrac%7B-15x%5E2%7D%7B-15%7D%20%2B%5Cfrac%7B6000%7D%7B-15%7D%20%5Cleq%20%5Cfrac%7B0%7D%7B-15%7D%20%5C%5C%20%5C%5C%20x%5E2-400%5Cleq%200%5C%3B%5BFactoring%5C%3Bon%5C%3Bleft%5C%3Bside%5D%5C%5C%20%5C%5C%20%28x%2B200%29%28x-200%29%5Cleq%200%20)
The possible solutions of the above inequality are given by the intervals ![(-\infty , -2], [-2,2], [2,\infty )](https://tex.z-dn.net/?f=%20%28-%5Cinfty%20%2C%20-2%5D%2C%20%5B-2%2C2%5D%2C%20%5B2%2C%5Cinfty%20%29%20)
. We need to pick test point from each possible solution interval and check whether that test point make the inequality 
true. Only the test point from the solution interval [-200, 200] make the inequality true.
The values of x which will make the above inequality TRUE is 
But we already know x should be positive, because time cannot be negative.
Conclusion:
Domain of the given function is 
X= 6/17or the alternative form is 0.352941
Answer:
Their best investment when they retire in 40 years would be option B.
Step-by-step explanation:
Ragai and Carly invest the $1000 received for their wedding for 40 years.
From the diagram,
In option A, the initial investment do not increase at a constant rate yearly.
In option B, the amount invested increase by $75 yearly.
In option C, the yearly increase does not have a steady value.
In option D, the amount invested increases by a n + consecutive odd values yearly. Where n is the increase of the previous year.
Their best investment when they retire in 40 years would be option B because it would yield the highest profit.
One dozen eggs is 48 eggs. Altogether that costs 40 dollars. If six of the eggs were broken then the money wasted would be 5 dollars.
The reason that it is 5 dollars is becuase it takes 10 to buy 12 eggs, and half of that is 6. So divide both 12 and 10 (separately) and you get 5 dollars for 6 eggs.
To get the percent you must divide 5 by 40.
The answer comes out to about 12.5% or 0.125.
So in the end, 12.5% of the money was wasted due to the broken eggs.
Hope this helped!
Your answer is 1 and 1/8 because 3/8x2 / 1/8
That's what makes your answer the last one 1 and 1/8
