• Best of luck to the class of 2024 for their HSC exams. You got this!
    Let us know your thoughts on the HSC exams here
  • YOU can help the next generation of students in the community!
    Share your trial papers and notes on our Notes & Resources page
MedVision ad

ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 unit (2 Viewers)

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Title says all, I'll be poasting questions and I hope you could help.

:)

You get cookies and stuff next study meat if you do.
 
Last edited:

deswa1

Well-Known Member
Joined
Jul 12, 2011
Messages
2,256
Gender
Male
HSC
2012
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

The instructions said you have to add "where he'll buy everyone a cookie". I'm not helping anymore...

Jokes- I'll do my best- post away
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

No cookies.

No help.
 

Fawun

Queen
Joined
Jun 23, 2012
Messages
1,270
Gender
Undisclosed
HSC
2014
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

Can I still get cookies without helping
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

Oh dear.
 

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

Fine people get cookies if they help me at the next study meat
 

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

and not the hungarian type
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

And by 'cookies', you mean the 'biscuit', right?

Ask away.
 

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

My first questions

Solve simultaneously

7/x-5/y=3 and 2/x+25/2y=12

and

9x^2+y^2=52 and xy=8
 

RealiseNothing

what is that?It is Cowpea
Joined
Jul 10, 2011
Messages
4,591
Location
Sydney
Gender
Male
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

My first questions

Solve simultaneously

7/x-5/y=3 and 2/x+25/2y=12

and

9x^2+y^2=52 and xy=8
For the second one, square the xy=8 to get (xy)^2 = 64. Then times the first equation by x^2 to get

Solve the resulting quadratic.
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

My first questions

Solve simultaneously

7/x-5/y=3 and 2/x+25/2y=12

and

9x^2+y^2=52 and xy=8
For the first one, make 5/y the subject for equation 1. Then sub into equation 2 because equation 2 is equal to 2/x+(5/2 x 5/y)=12. Solve for x then sub back in to equation 1 for y.

 
Last edited:

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

For the second one, square the xy=8 to get (xy)^2 = 64. Then times the first equation by x^2 to get

Solve the resulting quadratic.
I've reached this part, problem is I don't know how to solve it after this.
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

I've reached this part, problem is I don't know how to solve it after this.
He showed that x^2y^2=64, so replace x^2y^2 with 64 to be left with the quadratic 9x^4-52x^2+64=0. Then solve that quadratic (it's a reducible quadratic, let u=x^2)
 

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

He showed that x^2y^2=64, so replace x^2y^2 with 64 to be left with the quadratic 9x^4-52x^2+64=0. Then solve that quadratic (it's a reducible quadratic, let u=x^2)
Still not following (sorry if I'm being a pest)
 

Parvee

(╯°□°)╯︵ ┻━┻
Joined
Apr 4, 2011
Messages
1,077
Gender
Female
HSC
2012
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

Still not following (sorry if I'm being a pest)
9x^4-52^2+64=0
Letting u=x^2
9u^2-52u+64=0
and you can use your quadratic formula to find your u values
However u=x^2, solve for x
and sub into the original to find y
 

iBibah

Well-Known Member
Joined
Jun 13, 2012
Messages
1,374
Gender
Male
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un



Now just solve for u, then replace u with x^2 and solve for x.
 

Examine

same
Joined
Dec 14, 2011
Messages
2,376
Gender
Undisclosed
HSC
2013
Re: ITT we help examine to get 85 in his Maths extension 1 yearlies so he can do 4 un

Thanks so much guys!
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top