Answer:
Option D
Step-by-step explanation:
In the first three options we can evaluate the values of x with the help of Sine Rule for all the triangles
The Rule says
[tex]\frac{\sin A}{a}=\frac{\sin B}{b}=\frac{\sin C}{c}[/tex]
Where a , b and c are the sides opposite to the angles A, B and C of any ΔABC.
Hence , in order to determine unknown values of sides or angles , we need any 3 values from all 3 sides and 3 angles in a triangle. First Three options give us three values but the last option gives only 2.
Example
in first option we can apply Sine Rule as
[tex]\frac{\sin 84}{x}=\frac{\sin 63}{3}[/tex]
[tex]\frac{0.994}{x}=\frac{0.891}{3}[/tex]
[tex]x=\frac{0.991 \times 3}{0.891}[/tex]
[tex]x=\frac{2.973}{0.891}[/tex]
[tex]x=3.336[/tex]
