Question

Find the area of the polygon. Round to the nearest tenth.
30 cm- length
15 cm- height

Answer 1

626.7cm²

Explanation:

The area of the middle rectangular shape is simply 30(15) = 450cm²

As for the 2 semicircles, since they are congruent, we can just find the area of a full circle with the same radius.

As the diameter of each semicircle is 15cm, then the radius will be 15/2cm and hence the total area of both semicircles is π(15/2)² = (225/4)π. The area of the polygon is therefore 450 + (225/4)π cm²

Answer 2

626.7 cm²

Explanation:

Given:

Middle one is rectangle.

Area of rectangle is given by: length* breadth

Area of rectangle = 30*15=450 cm^2

Again

if we join two half circle it will make a circle.

Area of two semi circle =
`\sf \pi \:radius^2`

Here

Radius = 15/2 =7.5 cm

Now

aAre of two semi circle =
`\sf \pi 7.5^2=176.7 cm^2`

Now,

Total area = Area of rectangle + Area of two semi circle

Total Area
`\sf = 450 cm^2+ 176.7 cm^2`

Total area =
`\sf 626.7 cm^2`

Therefore, the area of the polygon is
`\sf 626.7 cm^2`