Question

a) Find the circumference of a circle whose radius Is 4 Inches. Round to the nearest tenth.b) Find the length of AB If m4ACB=60° and the radius of the circle is 4 Inches. Round to the nearest tenth.CKComplete your work in the space provided.

Answer 1

To solve part a, we going to need the circumference of a circle formula

$2\pi r$

Being r the radius of the circle

So for our case:

$2\pi\cdot4=8\pi$

Answer a: 8pi or 25.1

Now for the part b, we got

So let's set out this equation

$\frac{\frac{\pi}{3}}{2\pi}=\frac{\beta}{2\pi r}$

In this case, beta is the length of AB and pi/3 is the conversion to radians of 60

Solving we get

$\begin{gathered} \beta=\frac{\pi r}{3} \\ \\ \beta=\frac{4\pi}{3} \end{gathered}$

Answer b: 4pi/3 or 4.1889