Solving systems of equations using substitution y=2x-8 Y=5x-20

A ship sails 250km due North qnd then 150km on a bearing of 075°.1)How far North is the ship now? 2)How far East is the ship now

olga_2 [115]

Answer:

1) 288.8 km due North

2) 144.9 km due East

3) 323.1 km

4) 207°

Step-by-step explanation:

Bearing: The angle (in degrees) measured clockwise from north.

Trigonometric ratios

$\sf \sin(\theta)=\dfrac{O}{H}\quad\cos(\theta)=\dfrac{A}{H}\quad\tan(\theta)=\dfrac{O}{A}$

where:

$\theta$ is the angle
O is the side opposite the angle
A is the side adjacent the angle
H is the hypotenuse (the side opposite the right angle)

Cosine rule

$c^2=a^2+b^2-2ab \cos C$

where a, b and c are the sides and C is the angle opposite side c

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Draw a diagram using the given information (see attached).

Create a right triangle (blue on attached diagram).

This right triangle can be used to calculate the additional vertical and horizontal distance the ship sailed after sailing north for 250 km.

Question 1

To find how far North the ship is now, find the measure of the short leg of the right triangle (labelled y on the attached diagram):

$\implies \sf \cos(75^{\circ})=\dfrac{y}{150}$

$\implies \sf y=150\cos(75^{\circ})$

$\implies \sf y=38.92285677$

Then add it to the first portion of the journey:

⇒ 250 + 38.92285677... = 288.8 km

Therefore, the ship is now 288.8 km due North.

Question 2

To find how far East the ship is now, find the measure of the long leg of the right triangle (labelled x on the attached diagram):

$\implies \sf \sin(75^{\circ})=\dfrac{x}{150}$

$\implies \sf x=150\sin(75^{\circ})$

$\implies \sf x=144.8888739$

Therefore, the ship is now 144.9 km due East.

Question 3

To find how far the ship is from its starting point (labelled in red as d on the attached diagram), use the cosine rule:

$\sf \implies d^2=250^2+150^2-2(250)(150) \cos (180-75)$

$\implies \sf d=\sqrt{250^2+150^2-2(250)(150) \cos (180-75)}$

$\implies \sf d=323.1275729$

Therefore, the ship is 323.1 km from its starting point.

Question 4

To find the bearing that the ship is now from its original position, find the angle labelled green on the attached diagram.

Use the answers from part 1 and 2 to find the angle that needs to be added to 180°:

$\implies \sf Bearing=180^{\circ}+\tan^{-1}\left(\dfrac{Total\:Eastern\:distance}{Total\:Northern\:distance}\right)$

$\implies \sf Bearing=180^{\circ}+\tan^{-1}\left(\dfrac{150\sin(75^{\circ})}{250+150\cos(75^{\circ})}\right)$

$\implies \sf Bearing=180^{\circ}+26.64077...^{\circ}$

$\implies \sf Bearing=207^{\circ}$

Therefore, as bearings are usually given as a three-figure bearings, the bearing of the ship from its original position is 207°

8 0

2 years ago

Read 2 more answers

HLEPPPPPP thanks and whoevers answer i think is good than i will give them the CROWN

s2008m [1.1K]

Answer:

the answer is 136......... if u need explanation then plzz give me a brainliest

3 0

3 years ago

Joe started to save money to purchase a new game console. His savings at the end of the first week included a jar of 468 nickels

Ksenya-84 [330]

Answer:

0.05x + 0.10y = 34.40

x + y = 468

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

An isosceles triangle with congruent sides of 16.2 cm and a third side half that length

Zielflug [23.3K]

Answer: option iii

The perimeter of an isosceles triangle with congruent sides of 16.2 cm and a third side half that length is 16.2+16.2+8.1 = 40.5 cm

Explanation:

The perimeter of an isosceles triangle with congruent sides of 16.2 cm and a third side half that length is 16.2+16.2+8.1 = 40.5 cm

First side is = 16.2 cm

Second side is = 16.2 cm

Third side = half of 16.2 = 8.1 cm

The perimeter of an isosceles triangle with congruent sides of 16.2 cm and a third side half that length is 16.2+16.2+8.1 = 40.5 cm

7 0

3 years ago

Read 2 more answers

What is the mean of the data set? {11, 14, 15, 16, 16, 18, 20, 20, 22, 22} A. 11 B. 15.6 C. 17.4 D 18

Mademuasel [1]

Answer:

C. 17.4

Step-by-step explanation:

add all the numbers and then divide

11 + 14 + 15 + 16 + 16 + 18 + 20 + 20 + 22 + 22 = 174

then divide by the amount of numbers there is which is 10.

174/10 = 17.4

4 0

3 years ago