Perimeter?

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1 Answer
Nov 30, 2017

See a solution process below:

Explanation:

The shape in the problem, from a perimeter point of view can be divided into two parts: a 3 sided "square" and a semi circle.

Three Sided Square

Each side of the three sided square is 9 m therefore the perimeter of this section of the shape is:

#3 xx 9" m" = 27" m"#

Semi-Circle

The formula for the perimeter or circumference of a circle is:

#C = 2pir# or #C = pid# where #d# is the diameter of the circle or #2r# or twice the radius.

We know the diameter of the semi-circle is 9 m therefore the perimeter of a circle 9 m is:

#C = 3.14 xx 9" m" = 28.26" m"#

We now can divide this by 2 to calculate the perimeter of a semi-circle or a half circle:

#(28.26" m")/2 = 14.13" m"#

Total Perimeter

We add the perimeter of the two partial shapes to obtain the perimeter of the complete shape:

#27" m" + 14.13" m" = 41.13" m#

The shape has a perimeter of 41.13 m