Answer:
162m²
Explanation:
distance from corner to center = 1/2 of the diagonal
all sides are equal, and this has 4 sides, so it is a square
9m = 1/2 of diagonal
multiply both sides by 2 to isolate the diagonal
18m = diagonal
area of square = length²
length * √2 = diagonal
given the diagonal, we can find the length and then the area
length * √2 = diagonal
divide both sides by √2 to find the length
18m/√2 = length ≈12.7
square the length to find the area
area = 162 m²