Help find the area and perimeter for these two shapes! explain your reasoning aswell

1.179.17

Step-by-step explanation:

area of triangle= height*base/2=25.48

there are 4 triangles so multiply 25.48*4=101.92

Since it’s a regular octagon, all the sides are equal to = 4cm

Like shown above in the diagram, the sides of the octagon can be extended such that it forms a square.

According to Pythagorean theorem, x2 + x2 = 42; 2x2 = 16

x = √8cm

Total side length for the square= 4 + √8 + √8 = 9.657cm

Area of square= (9.657cm) 2 = 93.25cm2

Area of 4 triangles= 4 (1/2 * √8 * √8) = 16.0cm

Area of octagon, A = Area of square – Area of 4 triangles = 93.25 – 16.0 = 77.25cm2

now add 101.92+77.25=179.17