Find the volume of a regular tetrahedron of side 20 cm. (do not use the formula of finding the tetrahedron's volume)

If f(x)= sqrt4x+9+2, which inequality can be used to find the domain of f(x)?

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?

Write two point-slope equations for the line passing through the points (6, 5) and (3, 1)