The perimeter is 72 because all sides on a square are the same measurements so you just have to do 18 times 4 to get 72
try 60 becasue 75/5 is 15 so I multiplyied 4x15 and got 60
Answer:
x = π/4 and 5π/4
Step-by-step explanation:
Given the expression;
2cos²x - 1 = 0
2cos²x = 0+1
2cos²x = 1
cos²x = 1/2
cos x = ±√1/2
cos x = ±0.7071
x = arccos(±0.7071)
x = ±45 degrees
Convert to radians
Sence 180° = π rad
45° = x
x = 45π/180
x = π/4
If x = -45°
Since cos is negative in the 3rd quadrant
x = 180 + 45
x = 225°
x = 225π/180
x = 45π/36
x = 5π/4
Look all you have to do is with each question draw a line to the answer I am going to help you. Mark the 3rd question with answer A Mark the second question with b and the first one C I might be wrong with the first one. Hope this helps
