HSC Standard Mathematics Predictions / Thoughts (1 Viewer)

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What did you guys get for the decagon question?
Oke so, the hexagon had 10 equal sides and the perimeter was 80. So you first divide 80 by 10 and get 8.

Each side was 8cm (or whatever units it was in), then a total rotation would equal 360°, so you divide that with 10. So that's 36°. So we now know that each triangle has the outer side as 8cm and the angle opposite to it as 36°.

Then you do 180 - 36. And divide that answer by 2. To find the 2 other angels. (Equal sides = Equal angles). Then you use the Sine rule for whichever, getting you sides a and b.

You proceed to use the COSINE rule to find the area. 1/2 × a × b × Cos(C).

And then you times your answer with 10 anddd that's your answer.
 

PCNQQn2

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You proceed to use the COSINE rule to find the area. 1/2 × a × b × Cos(C).
I don't think so.

There was a simpler answer I read on facebook that a teacher posted there.
Split the triangle OAB down the middle.
You can then use right-angled trig to find the height of that triangle. (tan 18 = 4/x)
This gives you x=12.3107...

You then find the area of triangle OAB as 1/2 * base * height, i.e. 1/2 * 12.3107... * 8
Then multiply that by 10.

You actually don't need sine rule, cosine rule or area rule for it.
 
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For the garden question.
The max fencing wire you have is 900metres.

You use 2x + 3y = 900 ( think that's what it was). And then you do 3/5 times by 900 and you get 540. That's for the 2 long side (2y), so since we divide it by 2. And we get 270.

Then we do 2/5 times by 900. You get 360. That's for the short lines. BUT, there's THREE short lines, because there's an internal short side too. (We don't need that). So we do 360 divided by 3 and the answer is 120.

So part b) is x = 120 & y = 270(or the other way around don't remember.

Part c) you do 120 × 270 and the largest area you can get is 32,400.
 
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I don't think so.

There was a simpler answer I read on facebook that a teacher posted there.
Split the triangle OAB down the middle.
You can then use right-angled trig to find the height of that triangle. (tan 18 = 4/x)
This gives you x=12.3107...

You then find the area of triangle OAB as 1/2 * base * height, i.e. 1/2 * 12.3107... * 8
Then multiply that by 10.

You actually don't need sine rule, cosine rule or area rule for it.
Ohhh yh you can do that too
 

PCNQQn2

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For the garden question.
I had slightly different answers.
In part (a) use the graph to find the x values corresponding with A=30000. They are x=100 and x=200. x=200 is the larger of them.
Part (b) the largest value for A occurs at the vertex of the graph. This is half way between x=100 and x=200, i.e. x=150. Substitute x=150 into 3x+2y=900, then solve for y. This gives y=225.
Part (c) substitute x=150 into A=450x-1.5x^2. This gives A=33750, which is consistent with the maximum value of the graph.
 

teddy123

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what does EVERYONE think the band 6 cut-off will be this year
Honestly this new common content could mean anything for the cut off. I hope it is lower then normal accounting for the fact most of the cohort seemed to have struggled, if I was to guess I would say somewhere in the 80's
 

shaffy33

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What does everyone think the average for Standard Maths 2 would be this year a lot of teachers and students are indicating it would be well below the past years averages.
 

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what does EVERYONE think the band 6 cut-off will be this year
Anyone's guess. First there's the marking. Maybe they'll be a bit generous, or maybe they'll continue the hard line from the exam. Then there's the judging where they decide the cut-offs.

My fear is for the students that were just spooked by the complexity of a question and didn't write anything down. Unfortunately that's pretty easy to mark!
 

shaffy33

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What does everyone think the average for Standard Maths 2 would be this year a lot of teachers and students are indicating it would be well below the past years averages.
 

sarah10123

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What does everyone think the average for Standard Maths 2 would be this year a lot of teachers and students are indicating it would be well below the past years averages.
was gonna ask this too i'm not sure what do you think??
 

shaffy33

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Like literally everyone I asked felt the STD 2 paper extremely challenging, must more difficult the last years HSC paper, and a significant step higher in difficulty then all the trials they did as revision
 

shaffy33

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Yeah like some questions I just did not understand, a lot of my maths teacher felt the exam was unfairly difficult, this was supported by many students and teacher across the state, like the wording technicality and some things that the teachers did the prepare their students as they had no clear indication from NESA about this type of difficulty, plus on top of that my school received a bomb threat whilst I was doing Legal which was going soo good...
 

shaffy33

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Yeah I am fine thank God, however I feel like luck is laughing at me, the easier exam which my teacher predicted 70% of the exam, one of the best Legal exam I have see 35 minutes left to go and this BS happens... Yeah this year has been truly a fat joke cant wait for it to end and hope 2021 would be more merciful haha. Like nearly 1/4 of the std exam was advance question which was higher then last year and bit too high like we choose standard for a reason
 

pinku bhaya

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ohhh that sucks - i'm sure NESA will figure something out with all the misadventures.
it will all be over soon!! how many exams do you have left? everyone's almost done now i can't wait to finish
yes exactly! i think they said something like 24 marks were common between standard and advanced which is not fair at all hahaha yes we're clearly in standard for a reason - did you get to mark your paper from the answers pdf?
lol i have 2 exams left and i got 51 for maths so feeling demotivated as hell
 

shaffy33

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Yeah nearly their, only have 1 exam left which is Business on Monday, marking my exam from the PDF puts me around 55-65%
 

pinku bhaya

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Yeah nearly their, only have 1 exam left which is Business on Monday, marking my exam from the PDF puts me around 55-65%
yea i hope whoever wrote that fucking paper gets a building dropped on their head, they deserve much worse for ruining our chances of getting into a good uni but oh well what can ya do. what do u wanna do in uni anyway
 

teddy123

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I cant seem to find the answers pdf, does anyone know where it is?
 

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