Respuesta :
Answer:
correct option is C. 3.7 km
Step-by-step explanation:
given data
A to Port B = 4.7 km
lighthouse = N73°E
lighthouse = N31°E
solution
we get here first [tex]\angle[/tex] B and
here
[tex]\angle[/tex] A = 90 - 73 = 17°
[tex]\angle[/tex] B = 73 - 31 = 42°
and
sum of all angle 180° so
[tex]\angle[/tex] A +
17° + 42° + [tex]\angle[/tex] C = 180°
solve it we get
[tex]\angle[/tex] C = 121°
Now we use here sin law that is
[tex]\frac{b}{sinB} = \frac{c}{sinC}[/tex] ........................2
put here value and we get
[tex]\frac{b}{sin42} = \frac{4.7}{sin121}[/tex]
solve it we get
b = 3,7 km
so correct option is C. 3.7 km

The ship has sailed about 3.7 kilometers. Option C is correct.
Given information:
The distance between Lighthouse A and port B is AB= z = 4.7 km.
The bearing of the port from the lighthouse is N73°E.
A ship has sailed due west from the port and its bearing from the lighthouse is N31°E.
See the attached figure with triangle ABC.
From triangle ABC,
[tex]\angle A=90-73=17^{\circ}\\\angle B=73-31=42^{\circ}[/tex]
Use the angle sum property to get the value of angle C as,
[tex]\angle C=180-17-42\\=121^{\circ}[/tex]
Let the length of sides of triangle be x, y, and z as shown in the image.
Use sine law to get the value of distance the ship has sailed,
[tex]\dfrac{y}{sinB}=\dfrac{z}{sinC}\\\dfrac{y}{sin42}=\dfrac{4.6}{sin121}\\y=3.6689\\y\approx 3.7[/tex]
Therefore, the ship has sailed about 3.7 kilometers.
For more details, refer to the link:
https://brainly.com/question/22225513
