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3 years ago

I’m struggling with this question , geometry

Mathematics

1 answer:

just olya [345]3 years ago

7 0

The exterior angles of a regular n-gon add up to 360º; here n = 9, so each exterior angle has measure (360/9)º = 40º.

Corresponding interior angles are supplementary to exterior angles (they add to 180º), so each interior angle has measure (180 - 40)º = 140º.

Bisect this angle by connecting any given vertex to the center of the nonagon. These connections split up the nonagon into 9 congruent isosceles triangles, each of which have base angles of 70º.

Split each triangle in half to make a total of 18 70º-20º-90º triangles with height h and base b. Then

sin70º = h/7 ==> h = 6.578

sin20º = b/7 ==> b = 2.394

and each right triangle has an area of approximately 1/2 b h = 7.874.

Multiply this by 18 to get the area of the nonagon: 141.7.

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write a function g whose graph represents a translation 2 units to the right followed by a horizontal stretch by a factor or 2 o

Alenkinab [10]

$\bf f(x)=&{{ A}}({{ B}}x+{{ C}})+{{ D}}
\\ \quad \\
y=&{{ A}}({{ B}}x+{{ C}})+{{ D}}
\\ \quad \\
f(x)=&{{ A}}\sqrt{{{ B}}x+{{ C}}}+{{ D}}
\\ \quad \\
f(x)=&{{ A}}(\mathbb{R})^{{{ B}}x+{{ C}}}+{{ D}}
\\ \quad \\
f(x)=&{{ A}} sin\left({{ B }}x+{{ C}} \right)+{{ D}}\\\\
f(x)=&{{ A}} \left|{{ B }}x+{{ C}} \right|+{{ D}}
\\\\
--------------------\\\\$

$\bf \bullet \textit{ stretches or shrinks horizontally by } {{ A}}\cdot {{ B}}\\\\
\bullet \textit{ flips it upside-down if }{{ A}}\textit{ is negative}\\
\left. \qquad \right. \textit{reflection over the x-axis}
\\\\
\bullet \textit{ flips it sideways if }{{ B}}\textit{ is negative}\\
\left. \qquad \right. \textit{reflection over the y-axis}$

$\bf \bullet \textit{ horizontal shift by }\frac{{{ C}}}{{{ B}}}\\
\left. \qquad \right. if\ \frac{{{ C}}}{{{ B}}}\textit{ is negative, to the right}\\\\
\left. \qquad \right. if\ \frac{{{ C}}}{{{ B}}}\textit{ is positive, to the left}\\\\
\bullet \textit{ vertical shift by }{{ D}}\\
\left. \qquad \right. if\ {{ D}}\textit{ is negative, downwards}\\\\
\left. \qquad \right. if\ {{ D}}\textit{ is positive, upwards}\\\\
\bullet \textit{ period of }\frac{2\pi }{{{ B}}}$

with that template in mind, let's see,

$\bf f(x)=|x| \implies \begin{array}{lllccll}
f(x)=&1|&1x&+0|&+0\\
&\uparrow &\uparrow &\uparrow &\uparrow \\
&A&B&C&D
\end{array}$

so, to shift it to the right by 2 units, simply set C = 2.
to stretch it by 2, set A = 1/2.

the smaller A is, the wider it opens, the larger it is, the more it shrinks.

5 0

3 years ago

1. Water is filling a bathtub at a rate of 7 gallons per minute. Complete the table of equivalent

ASHA 777 [7]

Answer:

amount of water: 7, 14, 21, 28, 35

time : 1,2,3,4,5

6 0

3 years ago

-9 - (18v - 5) = 2(7v - 16) - 3v

andrezito [222]

Answer:

v = 28/29

Step-by-step explanation:

- 9 - (18v - 5) = 2(7v - 16) - 3v

- 9 - 18v + 5 = 14v - 32 - 3v

- 18v - 14v + 3v = - 32 - 5 + 9

- 29v = - 28

v = -28 / -29

v = 28/29

6 0

3 years ago

An internet service provider changes an initial fee of $65 and $18 per hour of labor for office internet installation. Which equ

OlgaM077 [116]

<h2>Answer:</h2><h2>The total cost (C) charged by the internet service provider = $65 + $18(n)</h2>

Step-by-step explanation:

Initial fee charged by the servic eprovider = $65

Cost per hour of labor for office internet installation = $18

The cost per hour be $18

Cost per two hours = 18 * 2 = $36

Cost per n number of hours = $18 (h)

where h represents the number of hours

The total cost (C) charged by the internet service provider = $65 + $18(n)

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3 years ago

Sally will measure the length of a wall in both centimeters and meters. Will there be fewer centimeters or fewer meters? Explain

harkovskaia [24]

There would be fewer meter. Since 1 m=100 cm.

6 0

3 years ago

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