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Algebra help!
Simon - 27/2/14 at 04:40 PM

Folks

Youngest has now started algebra and I was crap at it at school and now 30 years later I forgot what little I learned then

Anyway, we have this (for eg)

4x + 65 = 9x + 10

x =

Could someone please remind me how to do it and the basic principles/rules behind solving.

Ta very much

ATB

Simon

owelly - 27/2/14 at 04:47 PM

Simplifying
4x + 65 = 9x + 10

Reorder the terms:
65 + 4x = 9x + 10

Reorder the terms:
65 + 4x = 10 + 9x

Solving
65 + 4x = 10 + 9x

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-9x' to each side of the equation.
65 + 4x + -9x = 10 + 9x + -9x

Combine like terms: 4x + -9x = -5x
65 + -5x = 10 + 9x + -9x

Combine like terms: 9x + -9x = 0
65 + -5x = 10 + 0
65 + -5x = 10

Add '-65' to each side of the equation.
65 + -65 + -5x = 10 + -65

Combine like terms: 65 + -65 = 0
0 + -5x = 10 + -65
-5x = 10 + -65

Combine like terms: 10 + -65 = -55
-5x = -55

Divide each side by '-5'.
x = 11

Simplifying
x = 11

me! - 27/2/14 at 04:48 PM

4x + 65 = 9x + 10

55 = 5x (9x-4x and 65-10)

X=11 (55/5)

Simon - 27/2/14 at 04:50 PM

Blimey! Thanks for expansive post

Will get the boy on it (and try to do it meself)

Cheers very much

Simon

cliftyhanger - 27/2/14 at 04:52 PM

Get all the xs on one side, all the numbers the other
I would take 10 from each side (you can do that, but you must do the same both sides)

4x + 65 = 9x + 10
4x + 55 = 9x
Now take 4x from each side
55 = 5x
Now divide by 5
11= x

Afraid this doesn't work well by typing......works better with pencil and paper.

steve m - 27/2/14 at 06:05 PM

I have to say there are some well F****ng clever barstewards on this site, and some real dense f*ckwits

my answer was Tuesday

perhaps im in the lower portion

Steve

ross05 - 27/2/14 at 06:10 PM

Steve me too.I got Tuesday Afternoon

plus 1.



cannot even find the plus sign on my keyboard.

[Edited on 27/2/14 by ross05]

yellowcab - 27/2/14 at 06:51 PM

My head hurts

Letters belong in English, Numbers belong in Mathematics

Slimy38 - 27/2/14 at 07:29 PM

I like Edmund Blackadder trying to explain maths to Baldrick...

I have two beans, and I add two more. How many do I have? Some beans...

No, what does it make? A very small casserole...

bi22le - 27/2/14 at 10:45 PM

If your son needs extra help then the bbc bitesize website is great.

im studing at OU for a BEng in engineering. Doing a maths module at the moment. I studied Alevel maths and this stuff is still hard going.

tilly819 - 27/2/14 at 11:31 PM

Check out the HELM workbooks,

You can download them from here

http://www.personal.soton.ac.uk/jav/soton/HELM/helm_workbooks.html

Hope this helps

If your lad wants to go into engineering then they will give him a very good start.


As said above.
Get all the X terms on one side and all of the constants onto the other. Just remember if you change the side you change the sign.

Tilly

blakep82 - 28/2/14 at 06:51 AM

quote:
Originally posted by steve m
I have to say there are some well F****ng clever barstewards on this site, and some real dense f*ckwits

my answer was Tuesday

perhaps im in the lower portion

Steve


I was doing some online aptitude testing for a job application, in the maths bit, it said you get a calculation to do, you get 20 secs to work it out, 10 secs to type in your answer then on to the next one. Do the practise questions first. Ok.

So practise questions were all like
20 × ? = 60
Great, 3!

4 × ? = 24
6, this is easy.

So on to the real one then. There 5 parts to it, 5 questions in each part, and once you start you can't stop it, you have to do it

Question 1
6 × 47 ÷ ? +6 = 74

Wait, what?!
(I know that wont really work out, but you get the idea)

The verbal reasoning part used all big words I'd never heard of, got 4/8 of the practise questions right, a message then said "if you feel you may need help due to disability or special needs, please email the address above" er, thanks

coozer - 28/2/14 at 01:43 PM

Bloody hell, I seem to remember being very good at it when I did the extra maths lesson instead of PE. I loved maths, found it all dead easy and came away with top honours from the comp and never looked back.. I mean I never looked back at it and never used it..

Now cant even remember how to spell it!