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Q3-4 hard? (1 Viewer)

cccclaire

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Poad said:
Grrrr.

Didnt get that bit. :\
yeh I didn't get it the first time. I kept trying to find the co-ordinates of T.

Then I tried it again at the end and got it out =].
 

samwell

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leoyh said:
how did everyone get 2 for the radius question. i keep seeming to get 3 o__o

A = 1/2Pr
1/2 (8-15) = 1/2 (8+15+17)r
therefore, r = 3?
i got 3 lol. the answer is 3 am pretty sure.
 

mathslover

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leoyh said:
how did everyone get 2 for the radius question. i keep seeming to get 3 o__o

A = 1/2Pr
1/2 (8x15) = 1/2 (8+15+17)r
therefore, r = 3?
yeh i got the radius of the 2nd circle as 3
 

yorkstanham

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nah the second circle's radius was 2, im 100% positive about this

0.5Pr = A

area was 36, (big trianlge minus the little triangle: 60 - 24)

therefore 0.5Pr = 36

P = 10 + 8 + 17 = 36

therefore 18r = 36

and r = 2
 

AkaiHanabi

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Question 4 was pretty easy. I didn't do biii because my mind blanked on me =/ 3 was a great question, I'm pretty sure I got it all right. The rest of the paper however... =(
 

midifile

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yorkstanham said:
nah the second circle's radius was 2, im 100% positive about this

0.5Pr = A

area was 36, (big trianlge minus the little triangle: 60 - 24)

therefore 0.5Pr = 36

P = 10 + 8 + 17 = 36

therefore 18r = 36

and r = 2
This.

People who got 3 probably used the area of the big triangle (the two triangles added together), although you were only meant to use the area of teh second triangle.
 

hon1hon2hon3

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For question 4 (iii) area of triangle = 4x , let the base be x.

use the equation from (ii) area = 8 + x + square root of 8 square + x square

equate the two , 4x = 8 + x + square root of (8 square + x sqaure)
(3x - 8) square = 8 square + x square
9x sqaure - 48x + 64 -x sqaure - 64= 0
8x sqaure - 48x = 0
divide both side by 8

x sqaure -6x=0
x ( x - 6) = 0

Since x is not zero , soo x is equal to 6.


for (iv) using the x we found , and using that right angle triagle , we can easily found the 3 side of the triangle. (patho therom)

i found them to be 10 , 17 and 9

and i found the area , by completing the graph into a rectangle, then minus the two corner triagnle and divide them by 2.

and i remember i found it to be 36.

soo 36 = Half Pr
72 = Pr
and adding 10,17AND 9 = u again get 36

So 72 = 36 r

So r =2 .

This is how i get 2. i dont think its 3. . .

*gosh , u guys reply fast @@ I did it the stupid"ish" way, still works >_>
 

leoyh

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yeah that sounds right. i stuffed up the first part with a stupid mistake and thus, got that wrong, which will carry to the bit after it
 

AkaiHanabi

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midifile said:
This.

People who got 3 probably used the area of the big triangle (the two triangles added together), although you were only meant to use the area of teh second triangle.
Yeah. It's 2, you're supposed to use the area of the new triangle, not the big triangle. I got 3/2 the first time, so i knew i did something wrong. After figuring it out, I had to laugh at the "not to scale" label ^^
 

karar

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hey guys how easy was that paper. it was a joke predicated mark 100+
 

karar

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yeh man, i go to malkalfahad.

the question were very intense but the marks allocation was totally shit.

but gettin there.
 

AkaiHanabi

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karar said:
yeh man, i go to malkalfahad.

the question were very intense but the marks allocation was totally shit.

but gettin there.
The questions weren't difficult per se, there just were a lot of them. I work reaaaaallllly slowly, so that's probably why I screwed up =/
 

mickeyj1990

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yessss i got 6 and 2 as well thank gawd! i thought it screwed up there, but i got it! sweet! yeht hta scale got me worried too i couldnt do 6 c for the life of me though
 

snowconesyum

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midifile said:
This.

People who got 3 probably used the area of the big triangle (the two triangles added together), although you were only meant to use the area of teh second triangle.
argh that's what i did!
 

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