I need help with number 6 please

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 is the value of x in the following equation. -x ^3/2 = -27

Someone me what is the area of this figure? 18m 18m 8m 16m