First symmetrically cut the pentagon to get 5 pieces. (So that you will get the idea that this polygon is divided into 5 triangles)
Then find the area of one of the triangles:
Area of Triangle = 
A =
× 4 × 10
A = 20 m²
To find the area of the whole pentagon shape:
A = 20 × 5 = 100 m²
<em>Hope it helps!</em>
Answer:

Step-by-step explanation:
1) 4(2a+p)=c+p+a
2) Expand: 8a+4p=c+p+a
3) subract a and 4p: 7a=c-3p
4) Divide: a=