The perimeter of a semicircle is 20.56 miles. what is the semicircle’s radius?

13.1 feet

Step-by-step explanation:

C = (1/2)πd

20.56 = (1/2)(3.14)d

20.56 = 1.57d

13.1 feet ≈ d

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl