Question

3. One method you can use to determine whether a triangle is a right triangle, given three side lengths, is to apply the Converse of the Pythagorean Theorem. Alternately, you can use trigonometric ratios. Show that the triangle in the diagram is a right triangle by using trigonometric ratios. (Be sure to show all work and/or reasoning.)

Answer:

Answer 1

you can always use the Pythagorean theorem to prove right triangles, just plug them in
a^2 + b^2 = c^2
and see if the expression on the left equal the right

Answer 2

Yeah but my teacher says to use trig ratios

Answer 3

kk, so what are the common trig ratios? Ex: you have 3, 4, 5

Answer 4

I don't know, I'm really bad at trig. Like the trig identities or is it the sq root of 2 over 2 for sine and cosine and then its 1 for tangent For 45-45-90 triangles

Answer 5

Anyway, my first post is the converse of the py. theorem, so you can use that

Answer 6

I mean, I know how to use the Pyth. Theorem but I have to use trig ratios and I don't really know how.

Answer 7

But the question allow you to use that proof... That method is the converse of the theorem

Answer 8

No, it just said one way of proofing is the converse but it says to show that its a right triangle using trig ratios.

Answer 9

In my opinion, "alternatively" means that you can solve with either method...

But anyway, to use the ratios, you have to know the pythagorean triples, and this method is a pain in the foot

Answer 10

Here's the list
http://www.mathsisfun.com/pythagorean_triples.html

Just look for the one with your dimensions. Remember that multiples of these ratios can also work (e.g. 6, 8, 10 also works because it's a multiple of 3, 4, 5)