Here is the information for the stem-and-leaf plot you gave:
Median: 5
Range: 10
Mean: 6.08
Mode: 8
I don't see where the answers you provided would fit with this at all.
We have the following equation:
x2 + 4x = - (y2 - 20)
Let's review step by step:
step 1:
x2 + 4x = -y2 + 20
Answer: OK
step 2:
x2 + 4x + 4 = -y2 + 20 - 4
Answer: Wrong
The correct step is:
x2 + 4x - 4 = -y2 + 20 - 4
Or equivalently:
x2 + 4x + 4 = -y2 + 20 + 4
Answer:
he did make an error in his work in step 2
C1000÷ct=w
you pretty much ×1000 and then ÷t and c
Answer:
The perimeter of the plaque is 28 inches.
Step-by-step explanation:
Given : A house number is displayed on a plaque in the shape of a regular 7-sided polygon. The area of the plaque is 70 squared inches. The perpendicular distance from a side to the center is 5 inches to the nearest inch.
To find : What is the perimeter of the plaque?
Solution :
The 7-sided polygon can be divided into seven triangles whose height, h is equal to the perpendicular distance from each side to the center.
The base of each triangle is equal to the length of a side, s.
The area of each triangle is 
The area of the whole polygon is 
Now, the perimeter of a regular 7-sided polygon is
.
Substitute in area,

We have given, 



The perimeter of the plaque is 28 inches.