Question

The length of the arc of semi circle is 15 cm calculate the area of the semi circle ?

Answer 1

Answer:

The area of the semi-circle is 35.8 cm².

Step-by-step explanation:

The length of the arc is given by:

$s = r\theta$   (1)

Where:

s: is the length of the arc of semi-circle = 15 cm

r: is the radius

θ: is the angle in radians    

Since we need to calculate the area of the semi-circle, the angle is:

$\theta = \frac{360}{2} = 180 = \pi$  

From equation (1) we can find the radius:

$r = \frac{s}{\theta} = \frac{15}{\pi}$    

Now, the area of the semi-circle is:              

$A = \frac{\pi r^{2}}{2} = \frac{\pi (\frac{15}{\pi})^{2}}{2} = 35.8 cm^{2}$

Therefore, the area of the semi-circle is 35.8 cm².

I hope it helps you!