Question

The moon forms a right triangle with the Earth and the Sun during one of its phases, as shown below:

Answer 1

A scientist measures the angle x and the distance y between the Earth and the Sun. Using complete sentences, explain how the scientist can use only these two measurements to calculate the distance between the moon and the Sun.

Answer 2

This is my answer so far:
The scientist should use the cosine function (cos = adj/hyp) because we already know the adjacent, and the hypotenuse is what we need to find. If we use cosine, we can find the hypotenuse while working with the problem.

Answer 3

@ganeshie8

Answer 4

Am I taking the right approach by using cosine?

Answer 5

yes cos x = y/distance Moon to Sun

Answer 6

Okay thank you! But, should I write anything else in my answer?

Answer 7

\[\cos(x) = (\frac{ y }{ hypotenuse })\]

Answer 8

And is this what you mean by "cos x = y/distance moon to sun"?

Answer 9

Just want to make sure I'm writing it correctly.

Answer 10

@triciaal are you there?

Answer 11

yes and may want to include something about why this relationship right angle importance not sure how to word it

Answer 12

Okay, but I'm not sure how to describe that. I just started doing trig. Can you give me a hint on what the relationship is?

Answer 13

what I am getting at is why the cosine rule

Answer 14

Oh, okay, but my class did not really teach me "rules" that relate to the trig functions. All they said was that cosine is the ratio of side adjacent the angle to the hypotenuse.