Aquadrilateral has angles that measure 63°, 89° and 121°. what is the measure of the fourth angle? a. 273° b. 93° c. 87° d. 27°

Hello! i hope this
since the cosine is the ratio of the adjacent side to the hypotenuse, you can see that cos 60° = ½. answer. according to the property of cofunctions (topic 3), sin 30° is equal to cos 60°. sin 30° = ½.

Ithink it is 52