Q6 (b) (ii) (1 Viewer)

[gerardk]

basic run through on how to do it please.

Thanks

(the 2nd part of it)

 

[Thomas_wow]

<BAY = < YAM .'. = < MCY

.'. AYB = <AYM = <MYC - all on straight line

.'. 180 = 3x

x = 60

.'. MCY = 30 (180 - 60 - 90)

ratio

YM : CM = 1:2

.'. MY : AC = 1:4

thats what i did anyway ;]... prolly completely wrong tho ;[...

 

[quarxer]

let <YAM = x
therfore <BAC = 2x
therfore <BCA = 90 - 2x (angle sum of triangle)
therfore 90 - 2x = x (congruent traingles)
x = 30
<BCA = 90 - 2(30)
=30

Is how i did it, hope its right

 

[acmilan]

i got YCM = 30 degrees

then in triangle AMY, tan30 = MY/AM
.'. AM = root3MY

AC = 2AM
.'. AC = 2root3MY
AC/MY = 2root3
MY/AC = 1/2root3

 

[gerardk]

quarxer - the second part asks for the ratio MY : AC - thats the part i need help with

ilovechildren - t results is 3U yeah? are you allowed to use 3U methods in 2U?

edit: hey yeah 1 : 2(root)3 is what i got too..if thats the right answer 3marks is alot to give for such a little question

 

[acmilan]

I dont know whether you can or cant but they probably would have to give you atleast part marks id think

 

[blackmagic219]

yeah i got the same as gerark and acmilan 1987.....few it thought that was completely wrong...

 

[DeadFish]

Yup. I got 1:2root3 as well...

 

[Willmaker]

I used the sine rule.

Let YM=x and MC = y

x/sin30 = y/sin60 but since there are 2 lots of y
x/sin30 = 2y/2sin60

Therefore x/2y = ratio = sin30/2sin60

0.5/2(root 3)

But im probably wrong...... >.<

 

[coroneos]

1:2root3 = correct answer.

 

[Sweet_Lemon]

hum...think i got 1: 2(where's the root thino on this computer~~dam)3.....

should be rite then~~ let MY be 1 i think~~ makes life easier~~ ekekek

 

[gerardk]

so why 3 marks for it - i guess 1 mark for the correct angle, but for just saying its a 30 60 triangle and then sayin 1 : 2(root)3 isnt worth 2 marks..maybe they expect u to use the sine rule or whatever

 

[bevstarrunner]

I got the angle, then i identified that it was the 1:2root)3 triangle then went from there...I dont think they can mark you down for that...