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A trigonometry problem :S

a ladder 2.5m long leans against a vertical wall so that it makes an angle of 68(degrees) with the horizontal grounf. how far up the wall does the aldder reach ? give your answer to one decimal place.

^^ i have worked it out however im not fully convinced that my answer is correct as it looks odd. my answer was 0.9m by using cos
thankyou for any help.

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Reply 1

TenOfThem

It might be easier just to post your entire homework in one thread :smile:

Reply 2

TenOfThem

BTW your answer is wrong since the wall is OPPOSITE your angle

Reply 3

steve2005

Original post by silverose

You have found the distance from the wall to the foot of the ladder.

You need sin and not cos.

Reply 4

zeptobecki

sin x = opposite/hypotenuse
sin68= length/2.5

length=2.5sin68= 2.3m (2sf)

Reply 5

raheem94

Original post by silverose

See the diagram below:

Reply 6

MarshmallowBob

.....

(edited 12 years ago)

Reply 7

MarshmallowBob

#.\
#...\
#.....\
#.......\ 2.5m.......sin68= x/2.5
#.........\ ............x= 2.5Xsin68
#...........\...........x=2.3 m (1.dp)
#_____(68 \

(edited 12 years ago)

Reply 8

raheem94

Original post by MarshmallowBob

#.\
#...\
#.....\
#.......\ 2.5m.......sin68= x/2.5
#.........\ ............x= 2.5Xsin68
#...........\...........x=2.3 m (1.dp)
#_____(68 \

I think i posted a better diagram above :smile:

Reply 9

myfriendSQRT(-1)

Original post by raheem94

See the diagram below:

This picture made my day.

Reply 10

MarshmallowBob

Original post by raheem94

I think i posted a better diagram above :smile:

Lol i couldnt agree more :P i had wasted a good 5 mins with the diagram, then is saw your post, so i thought might aswell post it.

Reply 11

raheem94

Original post by myfriendSQRT(-1)

This picture made my day.

Lol

Reply 12

Hype en Ecosse

Original post by raheem94

Lol

I particularly enjoyed that you clarified where the wall was.

Reply 13

raheem94

Original post by Hype en Ecosse

I particularly enjoyed that you clarified where the wall was.

How do you enjoy a maths diagram?

Reply 14

Hype en Ecosse

Original post by raheem94

How do you enjoy a maths diagram?

The same way you enjoy anything? The notion that you had to clarify that the only vertical structure in the diagram was a wall made me smile.

Reply 15

raheem94

Original post by Hype en Ecosse

The same way you enjoy anything? The notion that you had to clarify that the only vertical structure in the diagram was a wall made me smile.

I just wanted to label the diagram. However, i didn't labelled the horizontal ground :biggrin:

Reply 16

silverose

Original post by TenOfThem

It might be easier just to post your entire homework in one thread :smile:

nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.

Reply 17

silverose

Thankyou so much for the patience with the diagrams guys .. really helped :biggrin:

Reply 18

raheem94

Original post by silverose

nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.

Its not a 'nasty comment'. Why can't you post all the questions in one thread?

We don't have problem with you not able to do your homework, but you were suggested to post all the questions in one thread rather than making multiple threads.

Reply 19

GreenLantern1

Original post by silverose

nobody's forcing you to help me .. don't like the fact that i can't do all my homework by myself but i'm trying to get help then keep scrolling and keep any nasty comments to yourself love.