387.5 centimeters (10 sides each the same length)
11.4 cm
15 cm * 6 sides = 90 cm perimeter
7 cm x 3 sides = 21 cm perimeter.
7 cm x 3 sides = 21 cm perimeter.
If it's a regular decagon then its perimeter is 10*25 = 250 cm
170 cm
Regular = all sides equal so all sides of 25 cm. Decagon = 10 sides. So perimeter = 10*25cm = 250 cm.
A decagon has 10 equal sides, so if the perimeter is 120 cm each side must be 12 cm
387.5 centimeters (10 sides each the same length)
100 cm
11.4 cm
15 cm * 6 sides = 90 cm perimeter
7 cm x 3 sides = 21 cm perimeter.
The perimeter is 7 cm
7 cm x 3 sides = 21 cm perimeter.
The perimeter of a triangle is the sum of its 3 sides.