Maths Help!!!! Please

[hidesy]

ok im in year 11 now, and in maths were currently doing "factorising trinomials" and im so confused about it.

so does any one out there know how to do it, if you do do you reckon you could give me the basics, we've been taught in the PSAB method so if you have any clue on how to do it please share

cheers

 

[Sam.]

Hmm Im currently doing that to, though im in year ten.

http://regentsprep.org/regents/Math/factor/Ltri1.htm

Try that, thats pretty much how I would explain it, without me doing all the writing

 

[cameron_15]

Hmm Im currently doing that to, though im in year ten.

Yeh, i'm in year 10 now and i beleive i learnt it last year.

 

[Sam.]

That doesnt suprise me at all, actually. Year nine and ten are both stage 5, and the teachers have the option of teaching topics such as trinomials to students in year nine or ten, however I think that you might be learning something new to you that we learnt last year awell. It varies from state to state, and even school to school

 

[Bomb446]

So you mean the ones where it's like x2(squared)-3x+2?
Which would be (x-2)(x-1)

 

[NCR600]

ok im in year 11 now, and in maths were currently doing "factorising trinomials" and im so confused about it.

so does any one out there know how to do it, if you do do you reckon you could give me the basics, we've been taught in the PSAB method so if you have any clue on how to do it please share

cheers

http://www.algebrahelp.com/lessons/factoring/trinomial/

I found this website helpful for brushing up on my maths stuff at uni.

Be aware though,that in mathematics, like everything else there's more than one way to skin a cat, and the best source of info & help is from your teacher, particularly if they're the one doing the marking.

 

[hidesy]

So you mean the ones where it's like x2(squared)+2x+2?

well an example would be: 6y^2 + 47y - 8
and the answer is (6y - 1)(y + 8)

 

[Booost]

Okay so here is a super simple one.

x² + 8x + 15

First off you need to find a number that add's to make eight and multiplys to make 15. In this case it is 5 and 3. 5 + 3 = 8 and 5 x 3 = 15.

x² + 5x + 3x + 15

Then you break the 8x into the two numbers you previously found (5 and 3)

x(x+5) + 3(x+15)

Next its as simple as factorising the equation.

(x+5)(x+3)

 

[Booost]

It gets a tiny bit more complicated when there are numbers in front of the x² but its still quite simple.

6y² + 47y - 8

This time you have to multiple the BLUE number by the LIME number first. This makes -48.
Now you must find a number which multiplys to make -48 and adds to make 47. This would be -1 and 48. -1 + 48 = 47. -1 x 48 = -48.

Break the 47 into these two new numbers

6y² + 48y -1y -8

Then factorise.

6y(y+8)-1(y-8)

(y+8)(6y-1)

 

[hidesy]

hey BOOST thanks heaps for you help, ill see if i can stair it down long enough so i get it

 

[bitterbro]

Ok i'm in year 12 and this stuff sucks but if you get good at it early, it's easy marks and you can blow your friends away

Here's a nice little party trick i learnt:

If you're talking about the stuff were you have a number infront of xsquared, say for eg.

2x^2 + 11x + 5 ------> mutliply the number infront of x^2 by the last and work from there
which makes it ..... 2x^2 + 11x + 10

= (2x^2 + 10x) + (1x + 5) just group

= 2x(x + 5) + 1(x + 5) common factors

= (2x + 1)(x + 5) voila