How do i do this? i'm failing geometry and i need to figure this out or i won't graduate.

Atriangle has side lengths of 15 inches and 30 inches. it also has angles that measure 45º and 20º. which of the following identifies the possible third angle of the triangle? a. 15 in., 65º b. 45 in., 65º c. 17 in., 115º d. 14 in., 115º

Just tell me how to set up the equation.

Someone me what is the area of this figure? 18m 18m 8m 16m