Ineed with number 30 and show work

30)

10 x 6 = 60
 11 x 4 = 44
12 x 4 = 48

60 + 44 + 48 = 152 cm^2

area = 152 cm^2

To find the area of a rectangle, the area equation is A= length X width. So you have to take all the rectangles and add the areas together to get the whole area of the polygon. 
So the left rectangle is 12 X 4 = 48. 
the middle bottom rectangle is 14 X 6= 84.
the top right triangle, is 5 X 4= 20. 

So then you add all of the areas together. 

48+84+20= 152. 

Area of the Polygon= 152 cm 

Im pretty sure it would be 6 purple rectangles.