Mountain climber Joe climbed to a mountain peak that was1200 feet above its base and 1500 feet east of its base. Mountain climber Bob climbed to a mountain peak that was 900 feet above its base and 1000 feet east of its base.

With #! i’ve tried to figure it out but i can’t.

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

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.