**Hello fellow Mathers**

( Intmath: Linear Equations: Example 2 (Link) )

I'm trying to figure out how exactly a specific equation works, where the guide tells me to do this example

3x+y= 10 [1]

x− 2y= 1 [2]

__Explanation given:__

If we subtract one row from the other row, we don't eliminate anything. However, if we multiply one of the rows, we can eliminate one of the variables by adding the rows.

**Row [1] ×2 gives us**

6x+ 2y= 20 [3]

x− 2y= 1 [2] (no change)

**If we add lines [3] and [2], we eliminate**

*y*.So x=3 and using line [1], y=1.7x=21

Check in line [2]: 3−2(1)=1

**[OK]**

So our solution is (3,1).

I don't understand why we multiply it. I see that if i try calculating it, i get an imaginary ( 2.714...) number. But if I double it, that doesn't change. Perhaps I also made a mistake in the calculation, but could not find it yet. (it's a simple one, you should be able to replicate in less than 1 minute).

Thanks in advance!