Question

Find the arc length of the semicircle.

Answer 1

Answer:

arc = 9π units

Step-by-step explanation:

the arc is half the circumference of the circle, then

arc = $\frac{1}{2}$ × 2πr = πr , then

arc = π × 9 = 9π

Answer 2

Answer:

$\boxed{\tt 9\pi }$

Step-by-step explanation:

What we want to find here is the arc length of 1/2 of a circle, we'll start by finding the of the circle.

Step 1:- find the circumference of the circle →

$\boxed{\sf Circumference\; of\; the \:circle=2\pi r}$

$\tt 2\pi \times 9$

$\tt 9\times 2\pi$

$=\tt 18\pi$

Step 2:- find the arc length of 1/2 of the circle →

The arc length is 1/2 of the circumference of the circle:-

$\boxed{\sf Circumference \; of \;\cfrac{1}{2}\; of\; the \; circle=\cfrac{1}{2}\times 18\pi}$

$\tt \cfrac{18}{2} \pi$

$\boxed{\tt 9\pi}$

Therefore, the arc length of the semicircle is 9π.