Composite figure is made up of 4 triangles and a square.
Area of Square = Length x Length 
Area of Square = 12 x 12 
Area of Square= 144 cm²
Area of triangle = 1/2 x base x height
Area of triangle  = 1/2 x 12 x 8 
Area of triangle  = 48 cm²
Area of 4 Triangles = 48 x 4
Area of 4 Triangles = 192 cm²
Total Area = 144 + 192 = 336 cm² 
[tex]\Longrightarrow \boxed { \boxed { Answer : 336 cm^{2} }}[/tex]