(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Solve for a, b, and c.

4c+6b+14a=25

6c+14b+36a=21

14c+36b+98a=105

2. Relevant equations

3. The attempt at a solution

I need to solve this without using matrices.

The easiest way would be to get it into row echelon form and back-substitute. However, I'm not sure how you can get this system of equations into row echelon form.

I can subtract 6 times the first equation from the third equation:

14c+36b+48a=105

- 24c+36b+84a=150

------------------------

-10c+0b+14a=-45

so you get:

-10c+0b+14a=-45

6c+14b+36a=21

14c+36b+98a=105

Next the only thing you could do would be subtract 7 times the first equation from the third equation, but if you did that you would be getting rid of the a term but reintroducing the b term which I just eliminated.

How do you get this into Row Echelon form to solve?

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# Homework Help: Solving A System of Equations

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