please help me with vivid explanation

Answer:
864 m²
Step-by-step explanation:
The area of a rectangle is given by the product of the length and the width
let A be the total area
A = 100*120
A = 12000 m²
Calculate the area of the small rectangles
Let A"' be the area of the road
A"' =A-A'
A"' = 12000-11136
A"' = 864 m²