Question

RMC is a 30°-60°-90° triangle and RM = 22 in. Find RC.

Answer 1

We can solve this with the trigonometric function cosine

`\cos \theta=(al)/(hy)`

where al is the length of the adjacent leg (side next to angle θ) and hy is the length of the hypotenuse.

By taking θ as the angle whose measure equals 60°, we replace RC for al and 22 for hy, then we get:

`\cos (60=(RC)/(22){}`

By multiplying both sides by 22, we get:

`\begin{gathered} 22*\cos 60=RC \\ RC=22\cos 60=11 \end{gathered}`

Then, RC equals 11