Answer:
Option B. 9.11
Explanation:
To find the length of line AB, we must first of all calculate the value of θ as shown in the attached photo.
The value of θ can be obtained as follow:
θ + 39° + 120° = 180° (sum of angles in a triangle)
θ + 159° = 180°
Collect like terms
θ = 180° – 159°
θ = 21°
Thus, we can obtain the length of line AB by using sine rule as illustrated below:
b/Sine B = c/Sine C
b = 16
Angle B = 39°
Sine C = 21°
c =?
b/Sine B = c/Sine C
16/Sine 39° = c/Sine 21°
Cross multiply
c × Sine 39° = 16 × Sine 21°
Divide both side by Sine 39°
c = (16 × Sine 21°) / Sine 39°
c = 9.11
Therefore, the length of line AB is 9.11