To calculate the volume of a triangular prism you have to multiply the area of the triangle (base) by its height using the formula:
[tex]V=A\cdot h[/tex]
The area of the base is A=24cm² and the length of the prism is h=9cm
[tex]V=24\operatorname{cm}^2\cdot9\operatorname{cm}=216\operatorname{cm}^3[/tex]
The volume of the prism is 216cm³
