Answer:
52.5 mm^2 (square millimeters)
Explanation:
Just split the figure into two sections to make a rectangle, and a right triangle (This whole figure can be thought of as a composite figure)
Once that is done, you will notice that the length and width of the rectangle is 9mm by 5mm, and the triangle is 3mm by 5mm (because 12mm - 9mm is 3 mm, and the height of the triangle is shared with the width of the rectangle).
The area of a triangle is 1/2(base×height) [just as a triangle is half of a rectangle], so the area of the rectangle is (length × width).
Therefore the 9mm by 5mm rectangle has an area of 9×5 mm = 45 mm^2, and the 3mm by 5mm triangle has an area of 1/2(5×3) = 15/2 = 7.5 mm^2.
Add both areas to find the total area:
45mm^2 + 7.5mm^2 = 52.5 mm^2.
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Or using the formula for the area of a trapezoid: A = h (b1 + b2) / 2
Where A is the area, b1 is the first base, b2 is the second base, and h is the height of the figure.
Given that our first base is 9, second base is 12, and our height is 5.
A = h ( b1 + b2 ) / 2 → A = 5 ( 9 + 12 ) / 2 → 5 ( 21 ) / 2 → 105 / 2 → 52.5
Then just put this quantity in mm^2 because it is the area of the figure in that unit.
→ 52.5 mm^2
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