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# linear equation watch

1. does this look right?

4(3x - 9) + 7 = x + 4
12x - 36 + 7 = x + 4
12x - 29 = x + 4
11x = 29 + 4
x = 3
2. yup
3. Yes.
4. Most definitely.
5. thanks, would it also be possible to check if i have done this correctly?

1/x = 4
1 = 4x
x = 1/4

<am i allowed to ask for people to check answers on tsr, or is that "breaking the rules" as such?>
6. (Original post by jermaindefoe)
thanks, would it also be possible to check if i have done this correctly?

1/x = 4
1 = 4x
x = 1/4
It's correct.

<am i allowed to ask for people to check answers on tsr, or is that "breaking the rules" as such?>
I don't think so it will breaking rule.
7. Well if you wanted to check whether you have done it right just substitute the value for x back in:

4(3x - 9) + 7 = x + 4

4(3*3-9)+7= 3+4

4*0+7=7

7=7
8. (Original post by jermaindefoe)
thanks, would it also be possible to check if i have done this correctly?

1/x = 4
1 = 4x
x = 1/4

<am i allowed to ask for people to check answers on tsr, or is that "breaking the rules" as such?>
Breaking which rules?

No, TSR is all about helping others! The only thing we object to is people giving us a question and saying "now wat" [sic]. Provided you've shown your working, or explained your thinking and what you're stuck on, someone will always be happy to help.
9. please could someone check my rearranging for this

i really suck at these and i did this from just looking at a guide so i havent really learnt it :s

y = mx + c (make x the subject)
y + c = mx
x = (y + c) / m
10. When you do something you have to do the same to both sides, ie Take c from both sides, not take from one and add to the other
11. (Original post by jermaindefoe)
please could someone check my rearranging for this

i really suck at these and i did this from just looking at a guide so i havent really learnt it :s

y = mx + c (make x the subject)
y + c = mx
U did wrongly.

It's y-c = mx
12. (Original post by SimonM)
When you do something you have to do the same to both sides, ie Take c from both sides, not take from one and add to the other
Exactly.

Like,
y = mx + c
y - c = mx + c - c
13. that was a silly mistake, so my answer is right, just i forgot to put a minus?

so x = y-c/m
14. Yes
15. so for

(ex)/d - g = f
(ex/d) = g + f
ex = d(g+f)
x = [d(g+f)]/2
16. Assuming e = 2
17. lol sorry about that - that was a typo

everything over E not 2

so if thats right it is time to

18. (Original post by jermaindefoe)
so for

(ex)/d - g = f
(ex/d) = g + f
ex = d(g+f)
x = [d(g+f)]/2

Yep, that's right. Just a typo in the last line, I think - you put /2 not /e.

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Updated: October 18, 2008
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