Given a cube with a volume of 18 cm3, what is the volume of a square pyramid that can fit perfectly inside the cube?

3cm

6cm

9cm

12cm

If volume of cube           =  18 cm³
then each side of cube  =   ∛18cm³
                                      ≈  2.6207

Volume of squared pyramid  =  
    since the pyramid fits perfectly in the cube then that means that
    there lengths and height are equal thus l² h =  18 cm³

∴   volume of pyramid  =  18 cm³  ÷  3
                                     =  6 cm

Thus B

The area below the line is shaded.
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The x-intercept of the boundary line is (-3/2,0)

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