How Do I Solve This Web Sheet Question

Please solve my maths question?

Q1: This is just the SA of the cube + area of side of cylinder
total SA = 6s² + 2πrh = 6 * 20² + 2π(7)(14) ≈ 3016 cm²

Q2: There might be a better way to do this, but I would determine the area and volume of the cone had it not been sectioned. If it has a base radius of 20cm and a radius of 8cm at 16cm, then the height of the "complete" cone would have been H such that
20/8 = H/(H-16) → 20H - 320 = 8H → 12H = 320 → H = 26.7 cm
The lateral area of this "complete" cone is π(20)√(20² + 26.7²) = 2094 cm²
The lateral area of the "lopped-off" part is π(8)√(8² + 10.7²) = 335 cm²
So the lateral area of the frustrum is the difference, or 1759 cm².
The area of the bottom of the bucket is π(8)² = 201 cm²,
for a total area of 1960 cm²

EDIT: I forgot the volume. The volume of the complete cone is
V = (π/3)r²h = (π/3)(20)²(26.7) = 11 170 cm³
The volume of the lopped-off part is v = (π/3)(8)²(10.7) = 715 cm³
Bucket volume is V - v = 10 455 cm³

Q3. A = 286 = πrL = π(r)(3r/7) = (3π/7)r²
r = 14.6 cm

How do I solve this web sheet question?

I'll give you some hints.

Read this:

http://en.wikipedia.org/wiki/Food_energy

Take note especially of the fourth paragraph

Using the information therein,calculate the kJ from each food type using the amount present in 1 lb and the relative proportion, e.g.

Fat:

(37 kJ/g)*(96 g/453.59 g)*(44 g) = 344.56 kJ

(1 lb = 453.59 g)

Then

Total kJ = kJ(fat) + kJ(protein) + kJ(carbohydrate)

Algebra 2 questions. this is for a practice sheet.. test monday. i need to see work cause i cant do them !!?

COMPLETING THE SQUARE:
x^2 +6x + 8 = 0
first, put the term without an x (8) on the other side
x^2 +6x = -8
then take 1/2 of 6, and make it part of the parentheses with x^2
(x+3)^2
you take 1/2 of six, because, if you were to multiply this term out (x+3)(x+3)...it would equal x^2 +6x +9
notice how 9 was added to the left side of the equation. because of this, you have to add 9 to the right side also. the equation will become
(x+3)^2=1
now, you must squareroot both sides to solve for x
x+3 = (+/- 1) **one can be either negative or posative because it was a sqare root (a negativexnegative is a posative...and a posativexposative is also posative)
so we try the equation both ways, and will have 2 solutions:
x+3= 1
x=-2
or
x+3=-1
x=-4
so the solution is either x=-2 or x=-4


QUADRATIC FORMULA
to use this, you need to memorize the formula.
if you are given the equation ax^2 +bx +c=0, you must know that
(-b (+/-) squareroot (b^2-4ac))/ (2a)
once you know this equation,all you need to do is plug in the numbers
example 1: x^2 -3x=40
a=1, b=-3, and c=-40
plug in the numbers

FIND VALUE OF DISCRIMINANT:
can't remember this- sorry!

Help setting up and solving this problem?

This problem might seem a little long, but I really need help. This is on the review sheet for my final exam, and my professor never taught us anything like this.

Your neighbor has 1000ft of fence with which to enclose a rectangular pasture for her horses. You already have an established fenced in pasture so she decides to use your fence as one of the four sides. (There is a picture of a rectangle, with "your fence" on one length, and her fence being the other length and two widths).
A) Find an equation that expresses the area of her pasture as a function of x, where x represents the length of her fence that is perpendicular to yours.
B) What is the "useable" domain of your function?
C) Find the dimensions of the largest pasture she can construct and its resulting area. [correct units on each].

If anyone could help me at all about going about solving this I would be really, really grateful!