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
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
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!
( 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
If we add lines [3] and [2], we eliminate y.6x + 2y = 20 [3]
x − 2y = 1 [2] (no change)
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!