Note: You missed to add some of the details of the question.
Hence, I am solving your concept based on an assumed graph which I have attached. It would anyways clear your concept.
Answer:
Please check the explanation.
Step-by-step explanation:
Given the right angled-triangle ABC as shown in the attached diagram
From the triangle:
Ф= ∠C = 30°
AB = 6 units
BC = y
tan Ф = opp ÷ adjacent
The opposite of ∠C = 30° is the length '6'.
The adjacent of ∠C = 30° is the length 'y'.
As Ф= ∠C = 30°
so
tan Ф = opp ÷ adjacent
tan 30 = 5 ÷ y
1 ÷ √3 = 5 ÷ y
y = 8.7 units
Therefore, the length of the unknown side length 'y' is 8.7 units.
