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#1 2005-12-29 00:09:35
- Anne54321
- Guest
Equation help
Hi
If MARGIN+PICNUM*(MARGIN+WIDTH)+MARGIN+WIDTH=PICW/2
then WIDTH= ?
Thanks
#2 2005-12-29 01:14:56
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Equation help
MARGIN+PICNUM*(MARGIN+WIDTH)+MARGIN+WIDTH=PICW/2
Put the additional MARGIN+WIDTH inside the brackets by factorising:
MARGIN+(PICNUM+1)*(MARGIN+WIDTH)=PICW/2
Put the MARGIN on the right-hand side:
(PICNUM+1)*(MARGIN+WIDTH)=PICW/2-MARGIN
Divide by (PICNUM+1):
MARGIN+WIDTH=(PICW/2-MARGIN)/(PICNUM+1)
Take away MARGIN:
WIDTH=[(PICW/2-MARGIN)/(PICNUM+1)]-MARGIN
Why did the vector cross the road?
It wanted to be normal.
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#3 2005-12-29 01:32:23
- krassi_holmz
- Real Member
- Registered: 2005-12-02
- Posts: 1,905
Re: Equation help
Why not
w=(pw/2-m)/(pn+1)-m
IPBLE: Increasing Performance By Lowering Expectations.
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#4 2005-12-29 03:05:41
- seerj
- Member
- Registered: 2005-12-21
- Posts: 42
Re: Equation help
MARGIN+PICNUM*(MARGIN+WIDTH)+MARGIN+WIDTH=PICW/2
Let m MARGIN p PICNUM x WIDTH q PICW
Then
m+p*(m+x)+m+x=q/2
px+x=q/2 -m -pm -m
x ( p+1 )=q/2-2m-pm
x= (q-4m-2pm)/2*(p+1)
x= (q-2m*(2+p)) / (2*( p+1 ))
WIDTH=( PICW-2MARGIN*(2+PICNUM))/(2*( PICNUM+1))
Last edited by seerj (2005-12-29 03:06:42)
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#5 2005-12-29 09:44:34
- Anne54321
- Guest
Re: Equation help
I have tried these equations in a computer program and I don't think they're yielding the correct answers.
If you take
MARGIN+PICNUM*(MARGIN+WIDTH)+MARGIN+WIDTH=PICW/2
and then use say MARGIN=10,PICNUM=7,WIDTH=10 and use these numbers to derive PICW
and then use one of the WIDTH solution equations with these numbers inserted they don't balance up ( by my reckoning!) Am I at fault or are these solutions ( which all yield the same answers) missing something ? Is it maybe a question of operator precedence?
#6 2005-12-29 11:01:31
- krassi_holmz
- Real Member
- Registered: 2005-12-02
- Posts: 1,905
Re: Equation help
IPBLE: Increasing Performance By Lowering Expectations.
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#7 2005-12-30 10:07:09
- Anne54321
- Guest
Re: Equation help
My mistake. It works perfectly. Many thanks for al your help. I've learnt a lot from you all.
#8 2005-12-30 10:10:18
- krassi_holmz
- Real Member
- Registered: 2005-12-02
- Posts: 1,905
Re: Equation help
You'll learn a lot from us.
IPBLE: Increasing Performance By Lowering Expectations.
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