Someone come in clutch and help a homie out

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

Two corresponding sides of two similar triangles are 3cm and 5cm. the area of the first triangle is 12cm^2. what is the area of the second triangle?

40) linda was making chocolate truffles for the first day of school. the recipe for 20 chocolate truffles is: i cup of cream 2 cups of dark chocolate she noticed this will not be enough truffles for the 42 sure that all students in each homeroom next year. to be sure that all students receive a truffle, linda must adjust her recipe. a. complete the recipe for 42 truffles cups of cream - cups of dark chocolate work: