Answer:
80 degrees
Step-by-step explanation:
The total sum of all angles is 180 in every triangle, 70 + 30 = 100, 180 - 100 = 80
The Answer is 80 degrees
answer is
cos(3x) = cos(2x+x)
= cos(2x) cos (x) -sin(2x)sin(x)
y=3x
12. Hope this helps!!!