Answer:

Step-by-step explanation:

Cos 300 = Cos ( 360 - 60)
= Cos 60

Answer:
10
Step-by-step explanation:
This triangle is isosceles, same as the little triangle.
If one side of the little triangle is 3x, then the little side with the tick (let's name it a) is also 3x.
That means the longer side, 2a, is 6x
This triangle is isosceles, so 6x = 4x + 20
Now, if we solve that, x = 10
The answer is 10
Hope this helps :)
Have a good day!
What it for like what subject
Sum of all three angles of a triangle must be equal 180.
Let's add all the the angles of the given choices to get the correct answer.
A: 45+60+75=180
Sum of 45°,60°, and 75° is 180°. So, A is the correct answer.