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Gcse maths question help

Chittesh14

I need help on a gcse question can you guys please help me 😀 topic - angle between a line and a plane

Reply 1

Chittesh14

Original post by Chittesh14

I need help on a gcse question can you guys please help me 😀 topic - angle between a line and a plane

Here is the question and answer to part a I just can't work out part B 😞 sorry I know I worked part a in a dodgy way I can't explain it I know how to do it. But totally stuck on part b ImageUploadedByStudent Room1417904134.800064.jpg

ImageUploadedByStudent Room1417904134.800064.jpg

ImageUploadedByStudent Room1417904146.616914.jpg

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Reply 2

lorealblab

would be a good idea to post your question, so we know whether we can help you or not..

Reply 3

Chittesh14

Original post by lorealblab

would be a good idea to post your question, so we know whether we can help you or not..

The question is in the picture part b

(edited 9 years ago)

Reply 4

TeeEm

Original post by Chittesh14

The question is in the picture part b

if your OM is correct

find the length by Pythagoras on the floor and then use trigonometry on the triangle OME to find the angle OME

Reply 5

Chittesh14

Original post by TeeEm

if your OM is correct

find the length by Pythagoras on the floor and then use trigonometry on the triangle OME to find the angle OME

Sorry didn't get that 😒 can you please explain what u mean again if you don't mind like with a picture or so

(edited 9 years ago)

Reply 6

Toffo132

Original post by Chittesh14

Here is the question and answer to part a I just can't work out part B �� sorry I know I worked part a in a dodgy way I can't explain it I know how to do it. But totally stuck on part b ImageUploadedByStudent Room1417904134.800064.jpg

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Well, for part a i got:
50²(the H of the right angle triangle)- 30²(half of the base) = 2500-900=1600
sqrt(1600) = 40cm = vertex 0 from bottom of pyramid
40cm + 60cm(height of cube) = 100cm = 1m

isn't this how part a is completed?

got it. seen where I went wrong, answer b would be:

OM² + EM²= OE²
86.5²+ 42.4²= 9114.41
sqrt 9114.41 = 95.5 (1dp) = OE

OEM = SIN^-1(OM/OE)
OEM = SIN^-1(86.5/95.5)
OEM = 64.91572432 = 65^o

So part b) = 65

(edited 9 years ago)

Reply 7

Chittesh14

Well if you draw a right angle from the bottom to the top it's m as the midpoint Lets say midpoint E to F is G so EG + GM is EM, which is the middle of the Base of the shape. So other than the cube 60 c, height to work out the height of the pyramid part you work out EM which is 42.4cm and then you do 50squared - 42.4 squared, square root it which gives you 26.5 cm ,add it to 60 cm cube heir making 86.5cm. This topic is angle between a line and a plane.

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Reply 8

Chittesh14

Original post by Toffo132

Thanks a lot for this bro. I don't know how I didn't figure this out, every time I'd make OE 110 cm knew I was wrong forgot to use Pythagoras or I'd have this answer ages ago. Thanks buddy 😃

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