The answer is 192 book. the reason why is because if you have 12 books each in 16 rows, you would like to MULTIPLY to find out how much in total. so
1
12
×16
---
72
+120
-------
192 books
The answer is true as the y value of y=sin
Check the picture below. so, that'd be the triangle's sides hmmm so let's use Heron's Area formula for it.
![~\hfill \stackrel{\textit{\large distance between 2 points}}{d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2}}~\hfill~ \\\\[-0.35em] ~\dotfill\\\\ (\stackrel{x_1}{10}~,~\stackrel{y_1}{5})\qquad (\stackrel{x_2}{15}~,~\stackrel{y_2}{15}) ~\hfill a=\sqrt{[ 15- 10]^2 + [ 15- 5]^2} \\\\\\ ~\hfill \boxed{a=\sqrt{125}} \\\\\\ (\stackrel{x_1}{15}~,~\stackrel{y_1}{15})\qquad (\stackrel{x_2}{30}~,~\stackrel{y_2}{9}) ~\hfill b=\sqrt{[ 30- 15]^2 + [ 9- 15]^2} \\\\\\ ~\hfill \boxed{b=\sqrt{261}}](https://tex.z-dn.net/?f=~%5Chfill%20%5Cstackrel%7B%5Ctextit%7B%5Clarge%20distance%20between%202%20points%7D%7D%7Bd%20%3D%20%5Csqrt%7B%28%20x_2-%20x_1%29%5E2%20%2B%20%28%20y_2-%20y_1%29%5E2%7D%7D~%5Chfill~%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%28%5Cstackrel%7Bx_1%7D%7B10%7D~%2C~%5Cstackrel%7By_1%7D%7B5%7D%29%5Cqquad%20%28%5Cstackrel%7Bx_2%7D%7B15%7D~%2C~%5Cstackrel%7By_2%7D%7B15%7D%29%20~%5Chfill%20a%3D%5Csqrt%7B%5B%2015-%2010%5D%5E2%20%2B%20%5B%2015-%205%5D%5E2%7D%20%5C%5C%5C%5C%5C%5C%20~%5Chfill%20%5Cboxed%7Ba%3D%5Csqrt%7B125%7D%7D%20%5C%5C%5C%5C%5C%5C%20%28%5Cstackrel%7Bx_1%7D%7B15%7D~%2C~%5Cstackrel%7By_1%7D%7B15%7D%29%5Cqquad%20%28%5Cstackrel%7Bx_2%7D%7B30%7D~%2C~%5Cstackrel%7By_2%7D%7B9%7D%29%20~%5Chfill%20b%3D%5Csqrt%7B%5B%2030-%2015%5D%5E2%20%2B%20%5B%209-%2015%5D%5E2%7D%20%5C%5C%5C%5C%5C%5C%20~%5Chfill%20%5Cboxed%7Bb%3D%5Csqrt%7B261%7D%7D)
![(\stackrel{x_1}{30}~,~\stackrel{y_1}{9})\qquad (\stackrel{x_2}{10}~,~\stackrel{y_2}{5}) ~\hfill c=\sqrt{[ 10- 30]^2 + [ 5- 9]^2} \\\\\\ ~\hfill \boxed{c=\sqrt{416}} \\\\[-0.35em] ~\dotfill](https://tex.z-dn.net/?f=%28%5Cstackrel%7Bx_1%7D%7B30%7D~%2C~%5Cstackrel%7By_1%7D%7B9%7D%29%5Cqquad%20%28%5Cstackrel%7Bx_2%7D%7B10%7D~%2C~%5Cstackrel%7By_2%7D%7B5%7D%29%20~%5Chfill%20c%3D%5Csqrt%7B%5B%2010-%2030%5D%5E2%20%2B%20%5B%205-%209%5D%5E2%7D%20%5C%5C%5C%5C%5C%5C%20~%5Chfill%20%5Cboxed%7Bc%3D%5Csqrt%7B416%7D%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill)
![\qquad \textit{Heron's area formula} \\\\ A=\sqrt{s(s-a)(s-b)(s-c)}\qquad \begin{cases} s=\frac{a+b+c}{2}\\[-0.5em] \hrulefill\\ a=\sqrt{125}\\ b=\sqrt{261}\\ c=\sqrt{416}\\ s\approx 23.87 \end{cases} \\\\\\ A\approx\sqrt{23.87(23.87-\sqrt{125})(23.87-\sqrt{261})(23.87-\sqrt{416})}\implies \boxed{A\approx 90}](https://tex.z-dn.net/?f=%5Cqquad%20%5Ctextit%7BHeron%27s%20area%20formula%7D%20%5C%5C%5C%5C%20A%3D%5Csqrt%7Bs%28s-a%29%28s-b%29%28s-c%29%7D%5Cqquad%20%5Cbegin%7Bcases%7D%20s%3D%5Cfrac%7Ba%2Bb%2Bc%7D%7B2%7D%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20a%3D%5Csqrt%7B125%7D%5C%5C%20b%3D%5Csqrt%7B261%7D%5C%5C%20c%3D%5Csqrt%7B416%7D%5C%5C%20s%5Capprox%2023.87%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%20A%5Capprox%5Csqrt%7B23.87%2823.87-%5Csqrt%7B125%7D%29%2823.87-%5Csqrt%7B261%7D%29%2823.87-%5Csqrt%7B416%7D%29%7D%5Cimplies%20%5Cboxed%7BA%5Capprox%2090%7D)
Answer:
374.1
Step-by-step explanation:
Area of Hexagon = 
The ' a ' is the side length.
So now we just plug in the values
= 374.12
172,000 is the answer I think