Answer:
72 square units.
Step-by-step explanation:
To find the area of the figure, we just need to find the area of the whole trapezoid and subtract the area of the small rectangle.
First, for a trapezoid of bases B₁ and B₂, and of height H, the area is:
A = (1/2)*(B₁ + B₂)*H
In the case of the image, the bottom base is 15 units long (each small square is a unit).
B₁ = 15 units
And the top base is 5 units long:
B₂ = 5 units
And the height is 10 units long.
H = 10 units.
Then the area of the trapezoid is:
A = (1/2)*(15 units + 5 units)*10 units = (1/2)*(20 units)*10 units
A = 100 square units.
The area of a rectangle of length L and width W is:
A' = W*L
In the graph we can see that:
L = 7 units
W = 4 units
A' = (7 units)*(4 units) = 28 square units.
Then the area of the figure is:
Area = A - A' = 100 square units - 28 square units = 72 square units.
