Solve the quadratic equation by the appropriate method.

x^2-81=0

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.

1.) 18+5 is one way i’m pretty sure there are others but i can’t think of them right now