B. 90. The perimeter is 30+30+15+15=90
Let's check.
x = 5π/24
4x = 5π/6
cos 4x = cos(5π/6) = cos 150° = -√3/2
cos² 4x = (-√3/2)^2 = 3/4
4 cos² 4x -3 = 4 (3/4) - 3 = 0
Answer: TRUE
Answer:
±35
Step-by-step explanation:
sqrt(49*25)=sqrt(49)*sqrt(25)=±7*±5=±35
The run can be made 11 meters long
