Question

Geometry Help!!

Answer 1

Finf FH

Answer 2

give me 5 minutes

Answer 3

are we missing some information? like an angle maybe?

Answer 4

no angle is given

Answer 5

except those 90 degrees

Answer 6

very tricky. I'll need more time to think

Answer 7

a clue: BS=EF-DE (there is a theorem like that in isosceles triangles)

Answer 8

where did you get that from?

Answer 9

a rule i don't know how to prove

Answer 10

there doesn't appear to be enough information to solve FH
Let me do some research and I'll get back to you

Answer 11

I need to clarify your drawing

Does HE = 10, HB = 5 & SB = 12 ?

Answer 12

OK, I've just worked out the base angles of the isosceles triangle so give me another 5 minutes or so and I'll have the answer to FH

Answer 13

I've got arctan2 as the base angles which is 63.4 degrees

Answer 14

I get FH= 7.99 which is close enough to 8

Answer 15

Have they given you an answer?

Answer 16

answer is 8

Answer 17

OK. Thats good, so my method is correct !!
I would assume you want to know how I got that?

Answer 18

of course i do

Answer 19

its long and quite complicated so I think its best that I write it out and send it to you as a pdf

Answer 20

@imqerty, what are you up to? if you're going to post the solution then i wont waste my time writing it out

Answer 21

m eating food :)
i ws doing it with coordinate geometry :)

Answer 22

have you managed to arrive at the same answer?

Answer 23

no i ws still working on it

Answer 24

OK, I'd be interested to see your approach. I'll go ahead and write out the geometric solution using algebra and post it up then

Answer 25

ok :)
i'll post the solution after food B)

Answer 26

please have a look at this question as well

Answer 27

hold your horses. I'm still writing out the solution to the last one

Answer 28

coordinate geometry is getting too complicated i think i shuld try another method :)

Answer 29

ok, stand by. I'm just about to post the solution

Answer 30

This corresponds to the drawing file attachment that you sent for A, B and C

Answer 31

WOW do we know tan2= x degrees in our memory in the exams :D thanks anyway..

Answer 32

haah :D nice solution
i ws doin something similar :) wait a sec ima post it

Answer 33

without using a calculator you could probably use sinα = 2/sqrt3 and cosα = 1/sqrt3 to work out FH from there. I reckon it can be done without working out a value for alpha

Answer 34

:) here-
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Answer 35

from eq 1 and eq2 we can get x and trigonometric values frm which we can calculate AF

Answer 36

Yes, I was right it can be done without evaluating α
sin(2α -90) = 2sin^2(α) -1 = 5/3

Answer 37

the second eq i got from this- BS=EF-DE

Answer 38

so you don't need a calculator