Answer:
The value of c is 12.25
Step-by-step explanation:
we know that
A perfect square trinomial is of the form

In this problem we have

so
equate the equations

we have
the following equations
-----> equation A
and
-----> equation B
<u>Solve the equation A</u>



<u>Solve the equation B</u>


therefore

The value of c is 12.25
The fence is 210 ft long.
There is a post every 3.5 ft.
If you divide 210 ft by 3.5 ft, you get the number of spaces between posts.
(210 ft)/(3.5 ft) = 60
The fence starts with a post. Then there is 3.5 ft of fencing. Then there is another post. Then there is another 3.5 ft of fencing followed by a post. In total there are 61 posts.
Here's another way of thinking of why you end up with 60 posts.
For each 3.5 ft of fencing, you place a post at the end of the fencing.
Since there are 60 3.5-ft-long pieces of fencing, there will be 60 posts, one at the end of each piece of fencing. The first thing that is done is to put the initial post before any fencing is put up. The first post plus 60 more posts add up to 61 posts.
Now that you see why there are 61 posts, we can calculate their cost.
61 * $8.50 = $518.50
The answer is 5,180! I used a calculator
First you add all the numbers together. So you add 82+93+75+89 to get 339. Once you get that, you divide it by the amount of numbers there are. In this case, it's 4. 339 divided by 4 is 84.75.
HOPE THIS HELPS!!