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Please Help, stuck with basic trig questions (1 Viewer)

Twickel

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Hi

A bike and car leave at same time. The bike travels on a bearing 80 deg and the car travels 15.7km on a bearing of 108 deg until the bearing of the bike from the car is 310 deg . How far has the bike travelled?

A boat is being followed by 2 ships, A and B 3.8km apart with A east of B. If A is on a bearing of 165deg from the boar and B is on a bearing of 205deg from the boat find the distance from the boat to both ships.


Please Help
 

Felix Jones

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oooh i can do it...but then ide have to get pen and paper....soz...just wait fro someon eless lazythan me.....Good Luck....i'll answer if no one else answers.
 

Twickel

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I know the answers I just dont know how to get them.

Just right the SIN formula or COS formula, with the right angles and numbers.
 

Twickel

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Yes, I just need to know the SIN or COS formula subbed in with the right angles and numbers. I need to know how they got it.
 

Felix Jones

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let the distance travelled by the bike be (x)


x/sin(22) =15.7/sin(50)
 

lyounamu

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Twickel said:
Yes, I just need to know the SIN or COS formula subbed in with the right angles and numbers. I need to know how they got it.
What do you mean by sine or cosine formulas?

Do you mean this?

sin (a+b) = sin(a)cos(b) + cos(a)sin(b)
sin (a-b) = sin(a)cos(b) - cos(a)sin(b)
cos (a+b) = cos(a)cos(b) - sin(a)sin(b)
cos (a-b) = cos(a)cos(b) + sin(a)sin(b)
 

Twickel

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THanks but no thats extension, thankyou though.

May I ask how you got the SIN 22?
 

Felix Jones

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the car travells at 108 degress true north...that's 90 + 18
when u draw anothet compass thingy for the car, the west east axes of both are parallel, but the bearing of the bike from the car is 310. so just draw that and u should be fine.....tell me how u post photos so i'll draw one for you.
 

Twickel

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Lol, it doesnt have to be perfect and straigh just a rough sketch.
 

Felix Jones

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lyounamu said:
LOL. I can visually imagine your struggle. :D
thank u for ur sympathy....wait a minute u didn't sympathize...u laughed..screw u jerk.lol.jking
 
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lyounamu

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MФëỹ™ said:
thank u for ur sympathy....wait a mnute u didnt sympathise...u laughed..screw u jerk.lol.jking
What a priceless statement.

By the way, why don't you do it with something else? Paint is not a good program to draw, is it?
 

Felix Jones

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im such a noob with computer...so no choice thast the simplest.lol
 

Felix Jones

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let the boat be P.

draw a triangle ABP.

if u draw properly, angle:
BPA=40
BAP=75 AND
ABP=65

also u know that AB is equal to 3.8.

so....PA/sin65 =3.8/sin40

similarly PB/sin75 =3.8/sin40

that should be it.
 

Twickel

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Ok, do 2 for me and ill give you karma. No piic required just right the formula.
 

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