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Maths help

Can you help me with this question please.
Show that
2x+x-3 px+q
Over (÷) can be written in over (÷)
X^(2) -8x+7 the form rx+s

Btw where it says over it is supposed to be a fraction but I don't know how to get it up on my phone.

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Do you mean:

show that:

can be written in the form
Reply 2
Original post by Maths1210
Can you help me with this question please.
Show that
2x+x-3 px+q
Over (÷) can be written in over (÷)
X^(2) -8x+7 the form rx+s

Btw where it says over it is supposed to be a fraction but I don't know how to get it up on my phone.


Get on the website and type it out, because I don't understand anything you've written. Just use / for divide and put the thing in the numerator in brackets and denominator in brackets.
Reply 3
Original post by StayWoke
Get on the website and type it out, because I don't understand anything you've written. Just use / for divide and put the thing in the numerator in brackets and denominator in brackets.


Show that (2x^(2)+x-3)/ (x^(2)-8x+7) can be written in the form (px+q) ÷ (rx+s) where p, q, r , and s are integers. (3 marks)
Reply 4
Original post by Maths1210
Show that (2x^(2)+x-3)/ (x^(2)-8x+7) can be written in the form (px+q) ÷ (rx+s) where p, q, r , and s are integers. (3 marks)


1.Factorise Numerator and Denominator
2.Eliminate common factors
3.???
4.Profit
Reply 5
Original post by StayWoke
1.Factorise Numerator and Denominator
2.Eliminate common factors
3.???
4.Profit


I got to 2x-3/-8x+7 by cancelling out the x^(2)'s but there has to be a number before both x's and I don't know how to make the bottom one positive without the top being negative.
Reply 6
Original post by Maths1210
I got to 2x-3/-8x+7 by cancelling out the x^(2)'s but there has to be a number before both x's and I don't know how to make the bottom one positive without the top being negative.


Madam you are not following my steps. Not only is your method incorrect, but you've also implemented it incorrectly.
Do you know what factorising is?
Reply 7
Original post by StayWoke
Madam you are not following my steps. Not only is your method incorrect, but you've also implemented it incorrectly.
Do you know what factorising is?


Yes putting an equation into brackets but I do struggle with the more complicated ones.
Reply 8
Original post by Maths1210
Yes putting an equation into brackets but I do struggle with the more complicated ones.


Can you factorise x^2-8x+7?
Do you know how to factorise quadratics?
Reply 9
Original post by StayWoke
Can you factorise x^2-8x+7?
Do you know how to factorise quadratics?


Is it (x-7) (x-1)?
Reply 10
Original post by Maths1210
Is it (x-7) (x-1)?


Cool can you factorise 2x^2 +x-3
Reply 11
Original post by StayWoke
Cool can you factorise 2x^2 +x-3


I'm trying but I'm struggling with this one.
Reply 15
Original post by Maths1210
Okay I got x (2x+3) + x(-2x-3)


That's not correct. Check your working. It's more helpful for me if you show your working, so I can tell you where you went wrong.
Reply 16
Original post by StayWoke
That's not correct. Check your working. It's more helpful for me if you show your working, so I can tell you where you went wrong.

ax^(2) + bx + c
2×-3= -6

3×-2 = -6
2x^(2)+3x-2x-3
X (2x+3) + x (-2x -3)
Reply 17
Original post by Maths1210
ax^(2) + bx + c
2×-3= -6

3×-2 = -6
2x^(2)+3x-2x-3
X (2x+3) + x (-2x -3)


3+-2= 3-2= 1 (x)
Reply 18
Original post by ben_dickinson
Do you mean:

show that:

can be written in the form


Yes.
You need to factorised the top and the bottom of the fraction, and then one of the brackets should cancel

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