Answer:
P=40
Explanation:
find the distance between each vertices:
between the following points to find the length of each sides, octagon has 8 sides , since it is regular pentagon the distance between each vertices =5
the length of each side of octagon=5
to check :d=√(x2-x1)²+(y2-y1)²
(-2,-4) and (1,0) , d=√[(1-(-2)]²+(0+4)² =√3²+4², d=5
(1,0) and (1,5) , d= 5
(1,5) and (-2,9) , d=5
(-2,9) and (-7,9) , d=5
(-7,9) and (-10,5) , d=5
(-10,5) and(-10,0) , d=5
(-10,0) and(-7,-4), d= 5
(-7,-4) and (-2,-4), d=5
perimeter of octagon = 8a ( a is the length of the side)
p=8(5)
P=40