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a factoring problem somethings not right

Hi all, I need some help, Im a old codger teachinv myself maths to help my son. I have attached a equation im not sure about. The negitive numbers are giving me a sore head :colondollar:

if you check my 2 brackets (-3+×) (-×+2) and expand them they don't match yet I think I have the right answer going by the text book.

http://1drv.ms/1cRLYv1

Please help this weary old silver haired C- grade maths lover.....

Reply 1

TenOfThem

Original post by silverpuma

Hi all, I need some help, Im a old codger teachinv myself maths to help my son. I have attached a equation im not sure about. The negitive numbers are giving me a sore head :colondollar:

You are trying to factorise 3x^2 - 8x + 4

Instead of dividing by 4, divide by -4

Reply 2

aoxa

Original post by silverpuma

Hi all, I need some help, Im a old codger teachinv myself maths to help my son. I have attached a equation im not sure about. The negitive numbers are giving me a sore head :colondollar:

You've mis wrote the question - when you times by your brackets, you should get 6(1-x) - 4(2x+1) = 6(2x+1)(1-x) where you've wrote 6(2x-1)(1-x)

And once you've divided by 4, times everything by -1 to get your x^2 positive. (Or just divide by -4 instead)

I don't think you'll be able to factorise it either - it looks like you'll need to use the quadratic formula.