Answer:
The correct answer is last option
Cos(55) = 11/x
Step-by-step explanation:
Points to remember
Trigonometric ratios
Sin θ = Opposite side/Hypotenuse
Cos θ = Adjacent side/Hypotenuse
Tan θ = opposite side/Adjacent side
From the figure we can see a right angled triangle, with one angle is 55 degree, one side is 11 and hypotenuse is x
To find the correct trigonometric formula
Here we have adjacent side of angle 55
Cos 55 = Adjacent side/Hypotenuse
Cos 55 = 11/x
Therefore the correct answer is last option
