Substitution Method:

When
3y - 2x = 11
y + 2x = 9

It becomes
3y - 2x = 11
y = 9 - 2x

Then
3(9 - 2x) - 2x = 11

And the equations are solved!
(27 - 6x) - 2x = 11
27 - 6x - 2x = 11
27 - 8x = 11
-8x = -16
x = 2

y = 9 - 2(2)
y = 9 - 4
y = 5

I hate mathematics, but this is one simple method that humans are unknowingly incorporating into their lives. To make things easier, they do substitution for products to make their lives go on. And substitutes tend to be more inferior to the actual desired product.

This applies to us humans as well:
The substitution method is used to eliminate one of the variables by replacement when solving a system of equations.

In other words, when one person is away or not gonna be around anymore, one would have to replace the gap of this person's existence to solve the problems and enable a smooth operation of workflow or the normal ongoing of another person's life. In fact, I have been a substitute for so many people in the company, that I wouldn't want to get myself mathematically equationed into my personal life. Blame it on my pride, blame it on my stubbornness, but I do not want to settle as the 2nd best or the alternate way out - that is just too unbearable. Because I am a unique product, to be appreciated for who I am.

Life has made me unsure of many things, I do not know what is the truth and what is not. I learnt to be less trusting, after being hurt again and again. I hate the feeling of being betrayed, which in turn led me to confine myself to my own secret garden. I just couldn't help it but to feel dubious about everything. But I am trying, at least I tried my best to break out of it every now and then. I guess time is the key to solve my problem.

But I did not play anyone out. I'm sorry if you feel that way but I really did not. It's not that you have think too much as well, coz I meant what I have said. I really want you to excel and be someone capable. As much as I would not want to admit, you are still one of the most important people in my life at the moment who understands me.