Help me with son's algebra, please!!

[Tyre Smoke]

Q. Write x2-6x+2 (x squared minus six x plus two for the avoidance of doubt here) as (x+a)2+b (x+a) squared plus b)

Ignore the bold that's just explaining what I've written, and can you show how you arrive at your answer please?

[sc0tt]

No idea but how old is your son? I’d be interested to see what age they are teaching him this.

[ILikeCake]

(x -6)X + 2

Can't show working, it's one step!

Edit, miss read question!

[handpaper]

Tyre Smoke said:

Q. Write x2-6x+2 (x squared minus six x plus two for the avoidance of doubt here) as (x+a)2+b (x+a) squared plus b)

Ignore the bold that's just explaining what I've written, and can you show how you arrive at your answer please?

x^2 - 6x + 2 (the caret ^ means "to the power")

Easier to consider it as (x+a)(x+a)+b = (x-3)(x-3)-7

The term in x (-6x in this case) will be 2a as x gets multiplied by it twice, the two results getting added together. b will be the difference between a^2 and the number you want, in this case, -7.

[bloomen]

It's time to make a stand through your son and get him to yell or write 'can't be bothered' every time algebra comes up.

I'd love to meet someone who ever made actual use of it in real life.

[Tyre Smoke]

He's Y10, 15yo. This is a mock GCSE paper as they are taking their maths a year early.

It's a bit of a long time ago since I did this, and can't get my head around it.

[sc0tt]

bloomen said:

It's time to make a stand through your son and get him to yell or write 'can't be bothered' every time algebra comes up.

I'd love to meet someone who ever made actual use of it in real life.

[jet_noise]

bloomen said:

It's time to make a stand through your son and get him to yell or write 'can't be bothered' every time algebra comes up.

I'd love to meet someone who ever made actual use of it in real life.

If you'd care to pop in and see me then you'll have met someone who does
(and I'm not a maths teacher!)

[Tyre Smoke]

handpaper said:

x^2 - 6x + 2 (the caret ^ means "to the power")

Easier to consider it as (x+a)(x+a)+b = (x-3)(x-3)-7

The term in x (-6x in this case) will be 2a as x gets multiplied by it twice, the two results getting added together. b will be the difference between a^2 and the number you want, in this case, -7.

Thanks!
So the answer is (x-3)^2-7 ?

[Speedy11]

If you would like to know more search for the term "completing the square".

[handpaper]

Tyre Smoke said:

Thanks!
So the answer is (x-3)^2-7 ?

Yep.

I did my GCSE Maths a year early too. Sometimes it still shows...

[sparkythecat]

[TwigtheWonderkid]

[bloomen]

jet_noise said:

If you'd care to pop in and see me then you'll have met someone who does
(and I'm not a maths teacher!)

You could be a shill implanted by mathematics teachers, or Russians of course.

[Planet Claire]

Speedy11 said:

If you would like to know more search for the term "completing the square".

This is what he needs to be revising to fully understand how to solve a quadratic by this method.

[Tony Starks]

bloomen said:

It's time to make a stand through your son and get him to yell or write 'can't be bothered' every time algebra comes up.

I'd love to meet someone who ever made actual use of it in real life.

I use the Pythagorean theorem all the time for checking things are square. And I failed maths too lol

[Saleen836]

I thought this was how kids did math these days...
https://www.youtube.com/watch?v=FSkooFyLt3g

[jet_noise]

bloomen said:

jet_noise said:

If you'd care to pop in and see me then you'll have met someone who does
(and I'm not a maths teacher!)

You could be a shill implanted by mathematics teachers, or Russians of course.

I know some people who have/had Russian wives, does that count

[bucksmanuk]

bloomen said:

It's time to make a stand through your son and get him to yell or write 'can't be bothered' every time algebra comes up.

I'd love to meet someone who ever made actual use of it in real life.

Almost every single working day for me....

[paua]

jet_noise said:

bloomen said:

jet_noise said:

If you'd care to pop in and see me then you'll have met someone who does
(and I'm not a maths teacher!)

You could be a shill implanted by mathematics teachers, or Russians of course.

I know some people who have/had Russian wives, does that count

How does one find the square root of a Russian wife?