what steps someone would take to use your method (substitution)

Question

and a clear argument stating the reason why your method is better than the other ones. (in other words, come up with a few good sentences that explain why you choose your method and why others should too!)

Answer 1

I have no idea why YOU chose substitution. However, here are ideas from a lot of other people.

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Answer 2

the teacher said i had to do substitution she said it was easier

Answer 3

Whether to use substitution or elimination becomes a judgement call. Sometimes one is easier, at other times not.

e.g.
2x + y = 15
3x +7y = 12

In this case , change the first to y = 15-2x and use substution, clearly easier

e.g

3x + 5y = 9
4x - 3y = 20

Here I would NOT use substitution
multiply 1st by 3 and the 2nd by 5 , then add

etc.

If one of variables has a coefficient of 1 or -1, then substitution is a good and quick method, otherwise it is not easier.