Question

How do you solve using gaussian elimination or gauss-jordan elimination, `-2x-5y=-15`, `-6x-15y=-45`?

Answer 1

`color(red)(x)=(-3y/2)+(15/2)`

Explanation:

[0]`-2x-3y=-15,-6x-9y=-45`
[1]`-2x=3y-15,-6x-9y=-45`
[2]`color(red)(x)=(-3y/2)+(15/2),-6x-9y=-45`
[3]#color(red)(x)=(-3y/2)+(15/2) ,-6((-3y/2)+(15/2))-9y=-45#
[4] `color(red)(x)=(-3y/2)+(15/2), 9y-45-9y=-45`
[5]`color(red)(x)=(-3y/2)+(15/2), -45=-45`
The best you can have is so a function of x and y.