how to do i need help solve

Answer:
51 cm^2
Step-by-step explanation:
We need to make this into pices that we can multiply to get are, luckily we have 2 parts we can seperate.
We can divide this into 2 shapes 9 by 4, and 3 by 5. all we need to do now is 9*4 + 3*5 to get 51 cm^2