Answer:
:)
Step-by-step explanation:
For simplicity I will substitue
for β.

In the first step I used the identity
And I factored out 
Then it's just simple algebra to cancel till the 3rd step where we used another identity derived from the Pythagorean Theorem.

That's it!
Answer:
Correct option: third one -> 12
Step-by-step explanation:
In a polygon with 'n' vertex, we can trace diagonals from one vertex to all vertices, except to the vertex chosen and the two adjacent vertices (because we would have sides and not diagonals), so we would have 'n - 3' diagonals.
If we have a polygon with 15 vertex, the number of diagonals from one vertex is 15 - 3 = 12.
Correct option: third one
Answer:
B. y=−5x+1152
Step-by-step explanation:
Answer:
y=1/4x-1
Step-by-step explanation:
Answer:
40
Step-by-step explanation:
you mutiply then take away the 2 last digits