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 
Answer:
Answers below
Step-by-step explanation:
1) 4 (x+4)
2) 4x + 16
3) 2x+8
4) 2x+8
5) 3x+9
Answer:
Step-by-step explanation:
1)a) Abscissa of O 0
Abscissa of A 4
Abscissa of B -3 {opposite of 3}
Abscissa of C 3 {3 is the only positive integer like A}
Abscissa of D -4.5
Abscissa of E -6
Abscissa of F -1 {Midpoint of AE = (6+4)/2 = 10/2 = 5th number from -6 or 4}
b) OB = 3 units
DA = 8.5 {4.5 +4 = 8.5}
(3, –2) and (6, 2)First, we must establish slope...m=(y-y1)/(x-x1)m=(-2-2)/(3-6)m=-4/-3m=4/3Point slope formula is...y-y1=m(x-x1)Let's select either coordinate. I randomly select the first (3, –2)...y--2=4/3(x-3)Subtracting a negative number is the same as adding a positive number...y+2=4/3(x-3)This corresponds to the first answer.Standard form...Ax+By=Cy+2=(4/3)x-4y=(4/3)x-6-(4/3)x+y=-6Multiply both sides by 3...-4x+3y=-18This also corresponds to the first answer. How about the second coordinate, (6, 2)...y-y1=m(x-x1)y-2=(4/3)(x-6)Let's convert it into standard form..y-2=(4/3)x-8y=(4/3)x-6-(4/3)x+y=-6Multiply both sides by 3...-4x+3y=-18
