Answer:
Area of house is 60.889 m²
Explanation:
Formula for right angle triangle is pyhtgoras
 a²= b² + c²
 a² =(3√2)² + (3√2)²
 a² = 17.99 + 17.99 
 a² = 35.989
 a =√35.99 ⇒ a = 5.999
Now secind triangle
 a² = b² + c²
 a² = ( 5.999)² + ( 5)² = 35.988 + 25 = 
 a = 7.908
So one side of the square is a
Area of square is = a²
 A = a² = (7.908)² = 60.998