A brother and sister are comparing their ages. The older sister is 8 years less than twice the brother’s age. The sum of their ages is 25 years. Let "x" be the age of the brother. Set up and solve an equation for x.

Theres no drop down menu

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.