Two coastguard station,Pand Q,are 25 km apart,Q is due east of P.A ship ,is at a distance of 18 km from P and 20km from Q.Calculate the size of angle SPQ

Respuesta :

Answer:

The size of angle SPQ is 52.4 degrees.

Step-by-step explanation:

Given:

Two coast guard station and a ship at a point from these coast guard.

That makes,three side length of a triangle.

Length of PQ = [tex]25[/tex] km

Length of  PS =[tex]18[/tex] km

Length of QS = [tex]20[/tex] km

We have to find the measure of angle SPQ.

Let the measure of SPQ be 'P'.

Using cosine law:

[tex]p^2=q^2+s^2-2qs\times cos(P)[/tex]

⇒ Plugging the values.

[tex]20^2=18^2+25^2-2\times 18\times 25\times cos (P)[/tex]

[tex]400=324+625-900\times cos (P)[/tex]

[tex]400=949-900\times cos (P)[/tex]

[tex]400-949=-900\times cos(P)[/tex]  ...subtracting 949 both sides.

[tex]-549=-900\times cos(P)[/tex]

[tex]\frac{-549}{-900}= cos(P)[/tex]                     ...dividing -900 both sides.

[tex]0.61=cos(P)[/tex]

[tex]cos^-^1(0.61)=P[/tex]

[tex]P=52.4[/tex] degrees

The size of angle SPQ = 52.4 degrees.

Ver imagen jitushashi143
ACCESS MORE
EDU ACCESS
Universidad de Mexico