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3 years ago

The area of a circle is 25pi m squared what is the circumference

1 answer:

8 0

$\bf \textit{area of a circle}\\\\
A=\pi r^2\quad 
\begin{cases}
r=radius\\
-----\\
A=25\pi 
\end{cases}\implies 25\pi =\pi r^2\implies \cfrac{25\pi }{\pi }=r^2
\\\\\\
25=r^2\implies \sqrt{25}=r\implies 5=\boxed{r}\\\\
-------------------------------\\\\
\textit{circumference of a circle}\\\\
C=2\pi r\qquad \qquad C=2\pi\left( \boxed{5} \right)\implies C=10\pi$

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3 years ago

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Could someone help me understand how to solve this?

monitta

Answer:

Amount in 4% account: $550

Step-by-step explanation:

Use simple interest formula $I=P\cdot r\cdot t,$ where

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t = time.

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3 years ago

The length of a swimming pool is 3 feet longer than it’s width. The swimming pool is surrounded by a deck that is 2 feet wide an

Firlakuza [10]

Answer:

The Length of swimming pool is 8.35 feet

The width of swimming pool is 5.35 feet

Step-by-step explanation:

Given as :

The length of swimming pool is 3 feet longer that its width

Let The width of swimming pool = w feet

So, The Length of swimming pool = L = (w + 3) feet

Now, The swimming pool is surrounded by deck of 2 feet wide

The width of deck = w' = w + 2 + 2 = (w + 4) feet

The area of deck = 116 feet²

The length of deck = L' = L + 2 + 2 = (L + 4) feet

So, L' = (w + 3 + 4) feet

I.e L' = (w + 7) feet

∵ The area of deck = 116 feet²

So , L' × w' = 116 feet²

(w + 7)× (w + 4) = 116

Or, w² + 4 w + 7 w + 28 = 116

Or, w² + 11 w - 88 = 0

Solving the quadratic equation as

ax² + bx + c = 0

So, w = $\dfrac{-b\pm \sqrt{b^{2}-4\times a\times c}}{2\times a}$

Or, w = $\dfrac{-11\pm \sqrt{11^{2}-4\times 1\times (-88)}}{2\times 1}$

Or, w = $\dfrac{-11\pm \sqrt{473}}{2}$

or, w = $\dfrac{-11\pm 21.7}{2}$

or, w = 5.35 , -16.35

The width of swimming pool = w = 5.35 feet

The Length of swimming pool = L = (5.35 + 3) feet = 8.35 feet

Hence, The Length of swimming pool is 8.35 feet

And The width of swimming pool is 5.35 feet

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3 years ago

What number will be multiplied to give -100 and be added to give 8

andrew11 [14]

Answer:

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Step-by-step explanation:

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2 years ago

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Answer:

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Step-by-step explanation: sorry if this wasnt what you were looking for.

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3 years ago