# Homework Help: How to solve this equation?

1. Aug 16, 2012

### electron5

How to solve this equation step by step?

m1a1 = m1g - T
-m2a2 = m2g - 2T
a1 = 2a2

How to solve a1, a2 and T?

2. Aug 16, 2012

### Staff: Mentor

Hi electron5. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif [Broken]

It looks like you have 3 equations in 5 unknowns, is that correct?

What would you consider as "the solution" to that? Usually, if you need to solve for 5 unknowns you'll need 5 equations to give that unique solution.

Better explain what you are trying to do, and where these came from.

Last edited by a moderator: May 6, 2017
3. Aug 16, 2012

### genericusrnme

Since this is an introductory physics question I'd guess it is, from looking at it, one of the basic newtons second law type questions, where m1 and m2 are known, so really it's three equations with three unknowns!

And to the OP, how do you usually solve systems of linear equations?
How would you solve the system;
x + 2y = 25
2 x +y = 20

Last edited by a moderator: May 6, 2017