Telephone poles are stored in a pile with 30 poles in the first layer, 29 in the second, and so on. If there are 12 layers, how many telephone poles does the pile contain?

294

Step-by-step explanation:

Given

First layer has 30 Poles

Second layer has 29 Poles

There are twelve layers

It follows an A.P. with first term and common difference

Sum of n terms of an A.P. is

Insert the values

So, there are 294 Poles in 12 layers

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40

i believe that the slope of the line is -5

step-by-step explanation: