Answer:

Step-by-step explanation:
To find the area of a triangle, we can use the formula of:

This formula comes from the area of a rectangle, because a triangle is half a rectangle.
A. The data in the table represent a function. y=x/2. This is seen as for every value of x in the table, y=x/2(half of it). You can show this further by trying this fact on each value.
B. For the original function, when x =8, y=x/2=4
For the function given in this part, when x=8, y=3(8)-10
y=24-10 y=14
This means the relation given in this part has a greater value when x=8
C. When x=80, f(x)=3(80)-10
=240-10
=230
The formula for an area of a regular parallelogram is:
A = l * w
Where,
l = length
w = width
We are given that the total measurement of fence is only
60 feet and one side of the house is used as one side of the pen. Therefore,
l + 2 w = 60
<span>or simplifying to make an explicit expression for
one variable, say l:</span>
l = 60 – 2 w
<span>Substituting to the 1st equation:</span>
A = (60 – 2 w) * w
A = 60 w – 2 w^2
<span>The maxima are obtained by getting the 1st
derivative then equating dA/dw = 0:</span>
dA/dw
= 60 – 4 w
60 –
4 w = 0
4 w
= 60
w =
15
Since
l = 60 - 2w
l =
60 – 30
l =
30
<span>Therefore
the dimension that will make the largest pen is 15 ft by 30 ft.</span>
<span>ANSWER: C</span>
We can always split a regular polygon with
sides into
triangles, whose base is the side of the polygon and whose height is the apothem of the polygon. So, the sum of the areas of all these triangles is

where
is the number of sides,
is the side length, and
is the apothem length.
So, you just need to plug you values in: in your case, you have 
So, the formula becomes
