# Thread: Need help on Right Triangles

1. ## Need help on Right Triangles

Hi. Tomorrow on going to get tested on right triangles. I have a problem that I cannot solve.
Can Anyone show me how do you it and give me some examples? Sorry if I'm posting this on a wrong forum.

3. ## Re: Need help on Right Triangles

21. Use cosine:

$\cos (54^{\circ}) = \frac{y}{28} \Rightarrow y = 28 \cos (54^{\circ}) \approx 16.46$ (meters)

4. ## Re: Need help on Right Triangles

Thanks. How do I close the thread now?