Answer:
84 cm³
Explanation:
The volume of a pyramid is given by the formula ...
V = 1/3Bh
where B is the area of the base.
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The base is shown as a right triangle with legs 8 cm and 7 cm. Its area is given by the triangle formula ...
A = 1/2bh
A = 1/2(8 cm)(7 cm) = 28 cm²
Then the volume of the triangular pyramid is ...
V = 1/3(28 cm²)(9 cm) = 84 cm³