Answer:
Area = 16
Step-by-step explanation:
The plan is to find the area of the large triangle (blue and white together) and subtract the white triangle's area.
Area of blue + white.
h = 8
b = 5 + 4
b = 9
Area = 1/2 * 8 * 9
Area = 1/2 * 72
Area = 36
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Area of white.
h = 8
b = 5
Area = 1/2 * 8 * 5
Area = 20
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Area of the shaded region (blue) = Area of both triangles - Area of the white
Shaded = 36 - 20
Shaded = 16
