Find the area of the square first
Area = Length x Width
Area = 12 x 9
Area = 108
Find the area of the right triangles
Area = 1/2(Length x Base)
Area = 1/2(9 x 2)
Area = 1/2(18)
Area = 9
Since there is 2 triangles multiply by 2
9 x 2 = 18
Now add
108 + 18 = 126
126 is your area