quote Simon the Nekonin

Jill and Milly have anchored their fishing dingies next to each other on a reef out at sea. Having caught their limit of whiting the girls each head off in the direction of their beach shacks. Jill heads for 4.2km on a bearing of 281 degrees, while Milly returns home on a bearing of 213 degrees for 3.7km. Draw a diagram, showing all known angles and lengths and then use the Cosine Rule to find how far Milly's shack is from Jill's shack.

Help please!

Damn, how the hell did you do that? Algebra 1 ftw

quote GhostMember

quote Simon the Nekonin

Jill and Milly have anchored their fishing dingies next to each other on a reef out at sea. Having caught their limit of whiting the girls each head off in the direction of their beach shacks. Jill heads for 4.2km on a bearing of 281 degrees, while Milly returns home on a bearing of 213 degrees for 3.7km. Draw a diagram, showing all known angles and lengths and then use the Cosine Rule to find how far Milly's shack is from Jill's shack.

Help please!

This is actually really easy. >_>


O is the starting point where they were fishing.
J is where Jill went off to.
M is where Milly decided to go.

<JOM = 281^o-213^o = 68^o

Cosine rule, when applied to this scenario should be:

JM² = OJ² + OM² - 2(OJ)(OM)(cos [<JOM])

JM² = (4.2)² + (3.7)² - 2(4.2)(3.7)(cos 68^o)
JM² = 17.64 + 13.69 - 31.08(cos 68^o)
JM² = 31.33 - 31.08(0.44)[2 d.p.]
JM² = 31.33 - 13.68 [2 d.p.]
JM² = 17.65
JM = 4.20 km [2 d.p.]

Let's take this for example:

       A
       /\
      /  \
     /    \
    /      \
   /        \
  /          \
 /____________\
B              C

Wow okay! I had no idea! That's pretty cool.

So if there is a cosine rule, is there also a tangent and a sine rule?

:/ If that question was from your text book, it should have the Sin and Cos rules.

sine rule:

  BC         AC         AB
------  =  ------  =  ------
Sin <A     Sin <B     Sin <C

It was slapped on the Practise exam, and we've never even been taught the Cosine rule or any other Trigonometry rules...

Are you like a Maths teacher or something? You know everything!

Hi everyone.

I got a new pet lama today. Cute little guy. I named him Leo.

What pets do you guys have? I have 1 cat, 1 dog, 8 goats, 12 chickens, 1 fish, and about 15 cows. Oh, and the lama.

Do you own a farm or something?

I love cats and dogs, but unfortunately I was never allowed one, since Dad though they would go in his vegetable garden and eat everything and piss on the vegetables.

Now that we have moved, I think I should ask if we can get one. I so hope we can!

So in General discussions you talk about math things and pets?

You read us like a book! Math things and pets.

Now let me check the forum's progress. I assume we all remember Pythagoras' Rule, correct? We discussed it on page 6. Now then, is {9,40,41} a Pythagoras Triplet? Remember, get this wrong and you lose your posting rights for three days.

Hmm... The Pythagoras Theorem? I'm sure that {9,40,41} is indeed a triplet.

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Are you like a Maths teacher or something? You know everything!

9x9 + 40x40 = 41x41 (I don't know how to use the superscript)
81 + 1600 = 1681
Yes, it is indeed.
3-4-5 is probably the triplet that you will need to know by heart. You should know a 3-4-5 just by sensing it, even without seeing it. Maybe not that extreme, but you get my point.

As for pets, I (my family) have/has a cat. I have an aquarium in my room with four fish that I just bought. I'm planning on buying more. I also have a small pond in my backyard with more fish in it. They've had so many babies that I don't know how many are in there.

Edit: I'm not sure what happened to my quote thing. The markup and whatnot got messed up.

This message was edited by FireEmblemFanatic on Jun 16 2008.

quote

quote

Are you like a Maths teacher or something? You know everything!

nono, he's asian. We just rock at math.

I don't... *hangs head in shame*

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I don't have any pets unless you count the unicorn in the backyard. But we did catch one of these buggers in the garden a few days ago.



I need a better camera.