Question

Work out the perimeter of a semicircle with radius 3 cm.
Give your answer in terms .

Answer 1

To find the perimeter of a semicircle you will need to find the circumference of a whole circle with a radius of 3 cm.  Then you would divide your answer by 2 or multiply it by 1/2.

C = pi x d
      3.14 x 6
C = 18.84 cm.

1/2 x 18.84 = 9.42 cm

The perimeter of the semicircle is 9.42 cm.

Answer 2

Answer:
perimeter = 15.42 cm

Explanation:
Semi-circle is defined as half a circle.
The formula used to compute the perimeter of the semi circle is:
perimeter = πr + 2r
where:
π is a constant = 3.14
r is the radius =  3 cm

Substitute with the givens in the above formula to get the perimeter as follows:
perimeter = π(3) + 2(3)
perimeter = 3π + 6
perimeter = 3(3.14) + 6
perimeter = 15.42 cm

Hope this helps :)