Answer:
D) 171 cm²
Step-by-step explanation:
You don’t actually need to decompose it. You could just do it as a trapezoid:
(15+23)/2=19
19x9=171
If you want to decompose it into 2 triangles and a rectangle:
10=15x9=135
1/2(3)(9)=13.5
1/2(5)(9)=22.5
135+13.5+22.5=171 also
