Answer:
Well you do what fraction says, 8 divided by 12 to get .6 repeating
Option A

<em><u>Solution:</u></em>
Given that we have to rewrite with only sin x and cos x
Given is cos 3x

We know that,

Therefore,
---- eqn 1
We know that,


Substituting these values in eqn 1
-------- eqn 2
We know that,

Applying this in above eqn 2, we get



Therefore,

Option A is correct
Answer:
BD = 12 :)
Step-by-step explanation:
Alright, we'll need the Pythagorean theorem for this!
So, the length of AC is 10. That means the lengths of AD and DC are both half of that, which is 5 :)
DC = 5
We already know that BC = 13, so we can plug in these values into the pythagorean theorem for the right triangle BDC:
BD^2 + DC^2 = BC^2
BD^2 + 5^2 = 13^2
BD^2 + 25 = 169
BD^2 = 169 - 25 = 144
BD = √144 = 12 :)
The sum of the angles of a triangle ALWAYS sum up to 180 degrees. So to find the other angle, you would take 180, subtract 90, and then subtract 26, to get 64.
The measure of the 3rd angle equals 64.