9514 1404 393
Answer:
A. 15 cm²
B. 15 cm²
Explanation:
A. Original Formula
The diagram shows the values of a, b, h. Put these in the original formula to find the area.
A = 0.5(a+b)h
A = 0.5(3 +7 cm)(3 cm) = 0.5(10 cm)(3 cm) = 15 cm²
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B. Splitting Method
The base of each triangle is half the difference between the two base lengths.
triangle base = (7 -3)/2 = 2 . . . cm
The area of a triangle is given by the formula ...
A = 0.5bh
A = 0.5(2 cm)(3 cm) = 3 cm²
The area of the central rectangle is given by ...
A = bh
A = (3 cm)(3 cm) = 9 cm²
Then the area of the trapezium is ...
A(triangle) +A(triangle) +A(rectangle) = A(trapezium)
(3 cm²) +(3 cm²) +(9 cm²) = A(trapezium) = 15 cm²
