What is x increased by 6

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

In the diagram, gef and hef are congruent. what is the value of x

The formula for the volume of a right square pyramid is given below, where a is the side length of the base and h is the height.