The answer is D! Hope this helps!
![\textit{area of a rectangle}\\\\ A=Lw ~~ \begin{cases} L=length\\ w=width\\[-0.5em] \hrulefill\\ L=a+5\\ w=a-2\\ A=60 \end{cases}\implies 60=(a+5)(a-2) \\\\\\ 60=\stackrel{F~O~I~L}{a^2+3a-10}\implies 0=a^2+3a-70 \\\\\\ 0=(a+10)(a-7)\implies a= \begin{cases} -10\\\\ 7 ~~ \textit{\LARGE \checkmark} \end{cases}](https://tex.z-dn.net/?f=%5Ctextit%7Barea%20of%20a%20rectangle%7D%5C%5C%5C%5C%20A%3DLw%20~~%20%5Cbegin%7Bcases%7D%20L%3Dlength%5C%5C%20w%3Dwidth%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20L%3Da%2B5%5C%5C%20w%3Da-2%5C%5C%20A%3D60%20%5Cend%7Bcases%7D%5Cimplies%2060%3D%28a%2B5%29%28a-2%29%20%5C%5C%5C%5C%5C%5C%2060%3D%5Cstackrel%7BF~O~I~L%7D%7Ba%5E2%2B3a-10%7D%5Cimplies%200%3Da%5E2%2B3a-70%20%5C%5C%5C%5C%5C%5C%200%3D%28a%2B10%29%28a-7%29%5Cimplies%20a%3D%20%5Cbegin%7Bcases%7D%20-10%5C%5C%5C%5C%207%20~~%20%5Ctextit%7B%5CLARGE%20%5Ccheckmark%7D%20%5Cend%7Bcases%7D)
notice, we didn't use the negative value, valid though as it is, because in this case "a" can't be negative.
The length of side BD, given that AD = 5 and CD = 20 is 10 (Option A)
<h3>Data obtained from the question</h3>
- Length of side AD = 5
- Length of side CD = 20
- Length of side BD =?
<h3>How to determine the length of side BD</h3>
Since the triangles are similar, we can obtain the length of side BD as illustrated below:
CD / BD = BD / AD
20 / BD = BD / 5
Cross multiply
BD × BD = 20 × 5
BD² = 100
Take the square root of both sides
BD = √100
BD = 10
Thus, the length of side BD is 10
Learn more about similar triangles:
brainly.com/question/25882965
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Answer:
about 5.37
Step-by-step explanation:
Geometric mean is
So square root of 12(2.4)
square root of 28.8 is
about 5.366563146
or 5.37