For some reason I can not even seem to draw the picture. The way it is described I thought it was a basic triangle, with angles 28,69, and 83. Tried using the law of sines to solve, but didn't come up with the correct answer. Any help appreciated.

# Chapter 3, problem 51.

**Ryan**- Admin
- Posts : 35

Join date : 2009-08-25

Age : 107

Location : Kennesaw

- Post n°2

### Re: Chapter 3, problem 51.

Hey Josh, I'll come back an post my diagram tomorrow when I'm near a scanner.

The only way I could figure out how to solve this was with the Law of Sines. However, my angles ended up being different. (58,41,81)

In the meantime maybe this will help:

You have -

Island A

Island B

Island C

Angle ABC = 58

Angle BCA = 41

Angle CAB = 81

Here's my first two steps of the problem...

1. draw initial vector (4.76, 37 degrees)

2. draw 2nd vector (from island 2 to island 3) The angle of this vector is 69 degrees from north, or 159 degrees total. However, that is the EXTERNAL angle of the triangle you are forming. You have to some minor geometry to get the internal angle. (you'll end up seeing this equation for angle ABC: 180-69-53 = 58 degrees) Hope that helps, but I will post the pic tomorrow.

The only way I could figure out how to solve this was with the Law of Sines. However, my angles ended up being different. (58,41,81)

In the meantime maybe this will help:

You have -

Island A

Island B

Island C

Angle ABC = 58

Angle BCA = 41

Angle CAB = 81

Here's my first two steps of the problem...

1. draw initial vector (4.76, 37 degrees)

2. draw 2nd vector (from island 2 to island 3) The angle of this vector is 69 degrees from north, or 159 degrees total. However, that is the EXTERNAL angle of the triangle you are forming. You have to some minor geometry to get the internal angle. (you'll end up seeing this equation for angle ABC: 180-69-53 = 58 degrees) Hope that helps, but I will post the pic tomorrow.

**Ryan**- Admin
- Posts : 35

Join date : 2009-08-25

Age : 107

Location : Kennesaw

- Post n°3

### Steps 1 and 2 for prob 51 ch 3

Josh- Posts : 4

Join date : 2009-08-26

- Post n°4

### Re: Chapter 3, problem 51.

This helped so much, thanks for your reply. I think my problem was where I was drawing the angles. Got mixed up with the west of north lingo.

**Ryan**- Admin
- Posts : 35

Join date : 2009-08-25

Age : 107

Location : Kennesaw

- Post n°5

### Re: Chapter 3, problem 51.

Glad that helped. Instead of doing a step by step for the rest, I'll just post my 'problem notebook' page.