2x - 6 = 20
2x = 20 + 6
2x = 26
x = 26/2
x = 13 <==
The length of material needed for the border is the perimeter of the backyard play area
<h3>How to calculate the
length of
material needed </h3>
The area of the play area is given as:

The area of a trapezoid is calculated using:

Where L1 and L2, are the parallel sides of the trapezoid and H represents the height.
The given parameter is not enough to solve the length of material needed.
So, we make use of the following assumed values.
Assume that the parallel sides are: 25 feet and 31 feet long, respectively.
While the other sides are 10.2 feet and 8.2 feet
The length of material needed would be the sum of the above lengths.
So, we have:


Using the assumed values, the length of material needed for the border is 74.4 feet
Read more about perimeters at:
brainly.com/question/17297081
Answer: 9.70%
Step-by-step explanation:
The formula to find the percentage error is given by :-

Given : Actual mass of zinc oxide used by pharmacist = 28.35 g
Estimated mass of zinc oxide used by pharmacist =31.1 g
Now, 
i.e. 
i.e. 
Hence, the percentage of error on the basis of the desired quantity.= 9.70%
Answer:
2pi?
Step-by-step explanation:
Pi is an irrational number so I guess double of pi would be irrational too.
2pi would be something like 6.28318531...