Answer:
580.4 cm^2 to the nearest tenth.
Explanation:
If we draw a perpendicular line from the top right vertex to the base we split the figure into 2 triangles and a rectangle in the center.
Left side triangle:
base = √(28^2 - 20^2) (using Pythagoras theorem
= 19.600
So its area = 1/2 * 19.6 * 20 = 196 cm^2.
Right side triangle:
Base = √(30^2 - 20^2) = 22.361
Area = 1/2 * 22.361 * 20 = 223.61 cm^2
Rectangle:
Base of rectangle = 50 - 19.6 - 22.361 = 8.039.
Area = 8.039 * 20 = 160.78.
So the area of the whole figure
= 196 + 223.61 + 160.78
= 580.39 cm^2.