I NEED HELP WITH THIS ASAP: *13 POINTS*

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

For what values of x is x2 + 2x = 24 true?

Idon’t understand! use slope intercept form to solve: through: (2,5) slope= undefined