Question 978203
30-60-90 triangles are
1-sqrt3-2 in size.
If the middle side is 9, the other leg is 9/sqrt(3) =9 *sqrt (3)/3= 3 (sqrt 3)

The area is 1/2 bh=(1/2)*9*3 sqrt(3)=(27/2)sqrt (3)=23.4 sq units