For the circle, a 70° central angle cuts off an arc of 8 inches what is the circumference of the circle (there are 360° in a circle)
there are 360° in a circle, now, this "sector" of the circle has an angle of 70°, so for 70°, there are 8in or circumference, or arc length
how much arc length or circumference in 360° then?
well \(\bf \begin{array}{ccllll}
degrees&circumference\\
-----&--------\\
70&8\\
360&x
\end{array}\implies \cfrac{70}{360}=\cfrac{8}{x}\)
solve for "x"
Answer: 41.14 inches
Step-by-step explanation:
The formula to find the length of an arc :-
\(l=C\times\dfrac{\theta}{360}\), where C is the circumference of the circle, \(\theta\) is the central angle cuts off an arc of length 'l'.
Given : Central angle : = \(\theta = 70{\circ}\)
Length of arc: \(l= 8\ inches\)
Now, substitute all theses value in the above formula , we get
\(8=C\times\dfrac{70}{360}\\\\\Rightarrow\ 8=C\times\dfrac{7}{36}\\\\\Rightarrow\ C=\dfrac{36\times8}{7}=41.1428571429\approx41.14\text{ inches}\)
Hence, the circumference of the circle is about 41.14 inches.