Answer:
option (4) is correct.
Step-by-step explanation:
Consider a triangle ABC with a, b and c are sides. and A, B and C are angles.
(Side a faces angle A, side b faces angle B and side c faces angle C)
According to Sine rule,
[tex]\frac{a}{\sin A}=\frac{b}{\sin B }=\frac{c}{\sin C}[/tex] ..........(1)
From the given triangle,
∠B = 79° , ∠C = 49°, c= 30 and b= x
We have find the value for x,
Consider the last two fractions of (1)
[tex]\frac{b}{\sin B }=\frac{c}{\sin C}[/tex]
Substitute the values given,
[tex]\frac{x}{\sin 79^{\circ} }=\frac{30}{\sin 49^{\circ} }[/tex]
[tex] \Rightarrow {x}=\frac{30 \times \sin 79^{\circ}}{\sin 49^{\circ} }[/tex]
On solving , we get x =39.02 (approx)
Thus, option (4) is correct
