Find the largest angle of ACDE.
D
50 mm
С
39 mm
53 mm
E

10

step-by-step explanation:

7+3=10

to find the perimeter, you add up all the lengths of the sides. in this case you would have to add up 18+22+40+80 which equals 160.

arc length = radius * x ( in radians)

6 * pi = 18 * x

divide by 18 on each side

6 pi / 18 = x

pi/3 = x

the angle is pi / 3 radians

or   60 degrees