Answer:
27cm²
Step-by-step explanation:
We should split this shape into 1 sqaure and 4 triangles.
For the square, it has length 3 and width 3 so the area is 9 square cm
For a triangle, it has the vertical height 3 and length 3. the formula for area of a triangle is ½bh. ½9 = 4.5. Since we have 4 triangles, multiply this by 4 to get 18 square cm.
18 + 9 = 27 so final answer is 27cm²