Please help my group isnt working

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

Thelime contains the point(-3,0) and parallel x-3y=3( show all work)

Henry is an avid reader, he devours 90 pages in half an hour how many pages has henry read per minute?