Hey there!!
In order to solve for the area, let's divide this figure into two rectangles.
Area of a rectangle = Length × Breadth
First rectangle at the top - Length = 8 and width = 3
Hence, the area would be = 24cm²
The second triangle measures : Length = 3 and the width = 5
Area = 3 × 5
... 15cm²
Total area = 24cm² + 15cm²
... 24 + 15 cm²
... 39cm²
Hope my answer helps!!