By the Pythagorean theorem
.. 15^2 = 10^2 +a^2
.. 225 = 100 +a^2
.. 125 = a^2
.. √125 = a
.. 5√5 = a ≈ 11.18
The missing side length is 5√5 cm.
Answer: ![A^{-1}=\left[\begin{array}{cc}\frac{3}{2}&-\frac{1}{2}\\-2&1\end{array}\right]](https://tex.z-dn.net/?f=A%5E%7B-1%7D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B3%7D%7B2%7D%26-%5Cfrac%7B1%7D%7B2%7D%5C%5C-2%261%5Cend%7Barray%7D%5Cright%5D)
<u>Step-by-step explanation:</u>
![\left[\begin{array}{cc}2&1\\4&3\end{array}\right]=\left[\begin{array}{cc}1&0\\0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%261%5C%5C4%263%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%260%5C%5C0%261%5Cend%7Barray%7D%5Cright%5D)
![\dfrac{1}{2}Row\ 1\rightarrow\left[\begin{array}{cc}1&\frac{1}{2}\\4&3\end{array}\right]=\left[\begin{array}{cc}\frac{1}{2}&0\\0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B2%7DRow%5C%201%5Crightarrow%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%26%5Cfrac%7B1%7D%7B2%7D%5C%5C4%263%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B1%7D%7B2%7D%260%5C%5C0%261%5Cend%7Barray%7D%5Cright%5D)
![Row\ 2 -4 \ Row\ 1\rightarrow \left[\begin{array}{cc}1&\frac{1}{2}\\0&1\end{array}\right]=\left[\begin{array}{cc}\frac{1}{2}&0\\-2&1\end{array}\right]](https://tex.z-dn.net/?f=Row%5C%202%20-4%20%5C%20Row%5C%201%5Crightarrow%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%26%5Cfrac%7B1%7D%7B2%7D%5C%5C0%261%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B1%7D%7B2%7D%260%5C%5C-2%261%5Cend%7Barray%7D%5Cright%5D)
![Row\ 1-\dfrac{1}{2}\ Row\ 2 \rightarrow \left[\begin{array}{cc}1&0\\0&1\end{array}\right]=\left[\begin{array}{cc}\frac{3}{2}&-\frac{1}{2}\\-2&1\end{array}\right]](https://tex.z-dn.net/?f=Row%5C%201-%5Cdfrac%7B1%7D%7B2%7D%5C%20Row%5C%202%20%5Crightarrow%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%260%5C%5C0%261%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B3%7D%7B2%7D%26-%5Cfrac%7B1%7D%7B2%7D%5C%5C-2%261%5Cend%7Barray%7D%5Cright%5D)
Think about it this way, what is 5x3??? 15 right. Ok then what is 5x30???? 150. So the store should sell each soccer ball for $5 each:)
Option C: 1 is the simplification of the expression 
Explanation:
The given expression is 
We need to simplify the given expression.
<u>Simplification:</u>
To simplify the given expression, let us apply the exponent rule,
where 
Thus, the the exponent rule
means that any value (except zero) to the power of zero is equal to one.
Thus, the expression
becomes,

Therefore, the simplified expression is 1
Hence, Option C is the correct answer.
The answer is test scores