You are Here: Home >< GCSEs

Rearanging formulae watch

1. Rearange: 84=m/n -9, to make n the subject of the formula, when i rearange this i get either: n= 93/m or n= m/93, which one is right?
2. (Original post by background)
Rearange: 84=m/n -9, to make n the subject of the formula, when i rearange this i get either: n= 93/m or n= m/93, which one is right?
Substitute you're answers into the equation to see which one is right.
3. 84 = m/n -9
To get n on its on, multiply both sides by n to get rid of the fraction, this should give you the following:
84n = m -9
Now divide both sides by 84, to get n on its own, this should give you the following:
n = m-9/84
4. One is right, one wrong. Show us your working.
5. (Original post by JTran38)
84 = m/n -9
To get n on its on, multiply both sides by n to get rid of the fraction, this should give you the following:
84n = m -9
Now divide both sides by 84, to get n on its own, this should give you the following:
n = m-9/84

93=m/n
93/m=n, or i can do your method, why is your method right and my method wrong?
6. (Original post by background)
93=m/n
93/m=n, or i can do your method, why is your method right and my method wrong?
I hope I'm doing this right _gcx . This is from my memory and it might be shoddy lel.

If I'm wrong ... Add 9 to both sides, then multiply n to get rid of the fraction and go from there.

P.S: Good I came across this and had a go
7. (Original post by chazwomaq)
One is right, one wrong. Show us your working.
93=m/n divide by m
93/m=n

method2:

93=m/n multiply by n
93(n)=m divide by 93
n=m/93
8. (Original post by background)
93=m/n
93/m=n, or i can do your method, why is your method right and my method wrong?
Remember this:

Whatever you do to one side of the equation, you MUST do to the other side.

Multiply BOTH side by n:

n now appears in both the numerator and denominator on the right hand side.

Any number divided by itself = 1

i.e.

hence

9. (Original post by background)
93=m/n divide by m
93/m=n
m/n divided by m is not n.
10. (Original post by background)
93=m/n divide by m
93/m=n
OK - here's your mistake. You didn't handle the RHS correctly.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: November 6, 2016
The home of Results and Clearing

2,218

people online now

1,567,000

students helped last year
Today on TSR

University open days

1. Sheffield Hallam University
Tue, 21 Aug '18
2. Bournemouth University
Wed, 22 Aug '18
3. University of Buckingham
Thu, 23 Aug '18
Poll
Useful resources

Study tools

Essay expert

Learn to write like a pro with our ultimate essay guide.

See where you can apply with our uni match tool

Make study resources

Create all the resources you need to get the grades.

Organise all your homework and exams so you never miss another deadline.

Resources by subject

From flashcards to mind maps; there's everything you need for all of your GCSE subjects.

Find past papers

100s of GCSE past papers for all your subjects at your fingertips.