What is the area of the given figure

So this figure is made up of half a circle and a triangle to find the total area
you find the area of half a circle, the area of a triangle then add it up
I supposed the radius is 3cm as it looks by the diagram
Area of a circle is pi r^2.
Plug in what we know and we get to the answer of the whole circle, we need only half of that. So the answer is 14.137
Then the area of the triangle which is the (b*h)/2
We get (3*4)/2---> 12/2 ---> which is 6
add them up and we have the total area as 6+14.137= 20.137
I think this is right. :)