# Have I rearraged this formula correctly?

1. Jan 28, 2010

### Gringo123

I have to make m the subject:

3(2m - t) = 2t + 7

This is my attempt:

m = (0.5t + 3.5 / 1.5) + 0.5t

2. Jan 28, 2010

### Staff: Mentor

Could you please show each step?

3. Jan 28, 2010

### Gringo123

sure
3(2m - t) = 2t + 7
move the 3 to the left side

2m - t = 2t + 7 / 3

move the -t to the left side
2m = (2t + 7 /3) +t

divide both sides by 2
m = (t + 3.5 / 1.5) +0.5t

and I realise this is slightly different to the 1st solution that I put up. 2t / 2 is of course t, not 0.5t.

Anyway, is it right?

4. Jan 28, 2010

### Staff: Mentor

No, it's not right. When you divide 7/3 by 2 you should get 7/6, not 3.5/1.5, which is equal to 7/3.

BTW, You really ought to learn which is left and which is right...

Also, in your second equation, the right side should have parentheses:
2m - t = (2t + 7)/3

In the following line you added parenthese, but they are not where you need them. This equation should be written like so:
2m = (2t + 7)/3 +t

Finally, the expression you have for m, besides being incorrect, should be written more simply, with the t terms combined.