Thread: simultaneous equations, 3 unknowns

Hey, need some help with the methodology involved in solving simultaneous equations with three unknowns.

I1 = I2 + I3
8I1= 3I3
3I1+5I2=3.4

cheers.

Originally Posted by clayson

Hey, need some help with the methodology involved in solving simultaneous equations with three unknowns.

I1 = I2 + I3
8I1= 3I3
3I1+5I2=3.4

cheers.

First rearrange your second two equations to get them with respect to

, therefore

For the second one, do the same:

, , so .

Now put these values of and in to your first equation, you now have an equation in terms of just .

Solve this and then put your value for back into the second and third equations to find all terms.