How do i solve this question 58−(14)2

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

The estimated number of people to attend the last bengals game of the season was 2000. the actual number of fans attending was 1200. by what percent did the estimate differ from the actual?

State if the two triangles are congruent. if they are, state how you know?