the solid is made up of 2 regular octagons, 8 sides, joined up by 8 rectangles, one on each side towards the other octagonal face.
from the figure, we can see that the apothem is 5 for the octagons, and since each side is 3 cm long, the perimeter of one octagon is 3*8 = 24.
the standing up sides are simply rectangles of 8x3.
if we can just get the area of all those ten figures, and sum them up, that'd be the area of the solid.
![\bf \textit{area of a regular polygon}\\\\ A=\cfrac{1}{2}ap~~ \begin{cases} a=apothem\\ p=perimeter\\[-0.5em] \hrulefill\\ a=5\\ p=24 \end{cases}\implies A=\cfrac{1}{2}(5)(24)\implies \stackrel{\textit{just for one octagon}}{A=60} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \stackrel{\textit{two octagon's area}}{2(60)}~~+~~\stackrel{\textit{eight rectangle's area}}{8(3\cdot 8)}\implies 120+192\implies 312](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Barea%20of%20a%20regular%20polygon%7D%5C%5C%5C%5C%20A%3D%5Ccfrac%7B1%7D%7B2%7Dap~~%20%5Cbegin%7Bcases%7D%20a%3Dapothem%5C%5C%20p%3Dperimeter%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20a%3D5%5C%5C%20p%3D24%20%5Cend%7Bcases%7D%5Cimplies%20A%3D%5Ccfrac%7B1%7D%7B2%7D%285%29%2824%29%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Bjust%20for%20one%20octagon%7D%7D%7BA%3D60%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Btwo%20octagon%27s%20area%7D%7D%7B2%2860%29%7D~~%2B~~%5Cstackrel%7B%5Ctextit%7Beight%20rectangle%27s%20area%7D%7D%7B8%283%5Ccdot%208%29%7D%5Cimplies%20120%2B192%5Cimplies%20312)
A) Add three <em>line</em> segments (AD, CF, BE) to the <em>regular</em> hexagon.
B) The area of each triangle of the <em>regular</em> hexagon is 35.1 in².
C) The area of the <em>regular</em> hexagon is 210.6 in².
<h3>How to calculate the area of a regular hexagon</h3>
In geometry, regular hexagons are formed by six <em>regular</em> triangles with a common vertex. We decompose the hexagon in six <em>equilateral</em> triangles by adding three <em>line</em> segments (AD, CF, BE).The area of each triangle is found by the following equation:
A = 0.5 · (9 in) · (7.8 in)
A = 35.1 in²
And the area of the <em>regular</em> polygon is six times the former result, that is, 210.6 square inches.
To learn more on polygons: brainly.com/question/17756657
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Answer:
- movie: $3.75
- video game: $5.75
Step-by-step explanation:
Two equations in two unknowns can be written:
3m +5v = 40
9m +7v = 74
These can be solved a variety of ways. One of them is using Cramer's rule. It tells you the solution to
is given by ...
- ∆ = bd -ea
- x = (bf -ec)/∆
- y = (cd -fa)/∆
For the numbers above,
- ∆ = 5·9 -7·3 = 24
- m = (5·74 -7·40)/24 = 90/24 = 3.75
- v = (40·9 -74·3)/24 = 138/24 = 5.75
The rental cost for each movie is $3.75; for each video game, it is $5.75.
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The attached graph shows a graphing calculator solution to these equations.
Answer:
21,40,42
Step-by-step explanation:
That's it.Wish it's correct.:D