Show that **x(squared)+4x+3/2** - **3x(squared)+1/6 = 6x+4/3 **

I've worked this out with bits of help - please email if need more detail to answer but what are these type of questions called so i can find some online? Or even better can anyone please come up with some of their own so i can try and answer them????

Thanks X

Posted Sun 3rd June, 2012 @ 12:46 by

ellie
amy, im not sure how u got to that conclusion because i think that u ae slightly wrong. i got the answer by doing the following. .....

(x^2 + 4x + 3) (3x^2 + 1)

------------------- _ -------------------- ==> multiply the right equation by 3

2 6

3x^2 + 12x + 9 (3x^2 + 1)

-------------------- _ -------------------- ==> same denominators therefore simplify

6 6

12x + 8

--------------- ==> can cancel out 2 from top and bottom

6

(6x + 4)

---------- ==> n that is ur answer

3

P.S thanks to amy for the inspiration to answer the question in that style ;D

Answered Sun 3rd June, 2012 @ 18:27 by

Braniac
I think they're just algebraic fractions. Go on mymaths or samlearning and they have quite a few questions to answer =)

Answered Sun 3rd June, 2012 @ 15:15 by

Joanne
I can't get it to equal 6x+4/3

But here's my attempt...

x^{2}+4x+3 3x^{2}+1

---------- - ----------

2 6

x^{2}/2 + 2x + 3/2 - x^{2}/2 + 1/6 = 2x + 4/3

Answered Sun 3rd June, 2012 @ 16:33 by

Amy
I think this is how you do it:

x₂ + 4x + 3 (times all by 6 and 3 so by 18) - 3x₂ + 1 (times both by 2 and 3 so by 6)

___________ ________

2 6

so you get:

18x₂ + 72x + 54 - 18x₂ + 6 this is just the left hand side of the equation

the right hand side:

= 6x + 4 (times both by 2 and 6 so by 12)

_______

3

= 72x + 48

so the equation reads:

18x₂ + 72x + 54 - 18x₂ + 6 = 72x + 48

simplify it to:

72x + 60 = 72x + 48

60 = 48

= 12

Hope it isn't too confusing, but it's hard to do on the computer :/

Answered Sun 3rd June, 2012 @ 19:25 by

Joanne
umm joanne, plzz dont take this to heart but i think ellie's question was Show that **x(squared)+4x+3/2** - **3x(squared)+1/6 ** **= 6x+4/3 **

**Not to solve it but nice to think round the box =D **

Answered Sun 3rd June, 2012 @ 20:10 by

Braniac
Oh sorry! Just shows that you need to read the question ;)

Answered Sun 3rd June, 2012 @ 22:06 by

Joanne
Yeah, what you did was exactly how I just did it :)

Answered Sun 3rd June, 2012 @ 22:11 by

Joanne
yh lol but u seem to went further then wot the question asked LOL XD ***

Answered Sun 3rd June, 2012 @ 22:23 by

Braniac
thanks guys! can anyone be even more helpful and come up with a similar question that i can solve just to get the hang of it???X

Answered Mon 4th June, 2012 @ 09:24 by

ellie
I have a 'solve' one for you:

Solve 4 3

_____ + _____ = 1

x + 3 2x - 1

Answered Mon 4th June, 2012 @ 19:23 by

Joanne
That is quite a easy question. firstly u want to find the lowest common denominator which is (x+3)(2x-1)

So what u do is u multiply everything by that common denominator and this is what u should get:

4 3

------- X **(x+3)(2x-1)** + ------------ X **(x+3)(2x-1)** = 1 X (x+3)(2x-1)

x+3 2x-1

Now u can see that there are some common factors that can be cacelled out like the denominators can cancel outwith the LCD u are multiplying by (the part in bold). Then u are left with this:

[4 X (2x-1) ] + [3 X (x+3) ] = (x+3)(2x-1)

Then expand the brackets and simplify!

11x + 5 = 2x^2 + 5x -3

Then make onee side equal zero so u get the following:

2x^2 - 6x - 8 = 0

Factorise the equation !!!!

(2x-8)(x+1)

therefore:

x=4 or x=-1

Answered Tue 5th June, 2012 @ 20:46 by

Braniac