Question

So I have a right triangle, all i'm given is the Hypotenuse and an angle. The Hypotenuse is 10, I need to find X, the Adjacent. I figured out all the angles and they are the following: 90, 36(given), and 54. I really can't figure this out and i need some guidance as i really don't understand cos, sin, and tan... at all.

Answer 1

Use law of sines.

Answer 2

(The sin of an angle)/(the length of the opposite sides) is the same for all the angles.

Answer 3

How would i find the sin of the angle, and which angle?

Answer 4

Look at this https://www.google.com.eg/imgres?imgurl=http%3A%2F%2Fwww.mathwarehouse.com%2Ftrigonometry%2Flaw-of-sines%2Fimages%2Fformula-picture-law-of-sines2.png&imgrefurl=http%3A%2F%2Fwww.mathwarehouse.com%2Ftrigonometry%2Flaw-of-sines%2Fformula-and-practice-problems.php&docid=SrCVSY5h23aL7M&tbnid=qomm7KSC6i1DyM%3A&w=561&h=378&bih=667&biw=1366&ved=0ahUKEwiUo8u4z7_NAhUMOsAKHdXvAbwQMwgdKAEwAQ&iact=mrc&uact=8

Answer 5

Use the calculator to get the sin of an angle.

Answer 6

that's not a right triangle, does that matter?

Answer 7

It is right.

Answer 8

that picture you sent me isn't a right triangle

Answer 9

Oh. It works for all triangles. Thought you were talking about your triangle.

Answer 10

https://www.mathsisfun.com/algebra/trig-sine-law.html

Answer 11

Oh, let me see if i can figure it out real quick...

Answer 12

Wait, so how exactly do I plug in the sides if I don't have them all?

Answer 13

You only need one.

Answer 14

The ratio is the same for all three angles. You're given three angles and a side.

Answer 15

sooo... Sin(54)|10 = Sin(36)|10 = Sin(90)|10

Answer 16

Is that right?

Answer 17

Oh no.

Answer 18

SOH CAH TOA

Answer 19

So then how would I do this?

Answer 20

\[\frac{ \sin90 }{ 10 }=\frac{ \sin36 }{ opposite(side) }\]Solve for (opposite side).

Answer 21

That's just for the first unknown side.

Answer 22

We'll do the same for the last unknown side.