Question

Find the perimeter of the composite figure.

A) 46.9

B) 42.9

C) 23.5

D) 31.9

Answer 1

A

Explanation:

half circle diameter = 9-(-1) =10

so perimeter = 2π r=20π =62.8

1/2 of it = 31.4

triangle 3 sides: 10, 4.5

10²+4.5² = long line's sqaure

so long line is 11

so perimeter for triangle without the line shared with semicircle = 11+4.5 =15.45

total =31.4+15.45 =46.85