How to find the missing measure of the cube with the volume?

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β

What effect would doubling all the dimensions of a triangular pyramid have on the volume of the pyramid? explain your reasoning.

Which of the following is the best first step in solving the equation below? 4+2㏒³x=17