Question

i am posting my question again,
as i didn;t get approprite answer
Why we can't linear equation of two variable ax + by+ c = 0 as
ax + by - c = 0 or
ax + by = 0

Answer 1

Why we can't write linear equation of two variable ax + by+ c = 0 as
ax + by - c = 0 or
ax + by = 0

Answer 2

I don't see a lot of difference between ax+by+c=0 and ax+by-c=0. It is just what you pick.

E.g.: take the equation 2x-5y-4=0
If you're in to ax+by+c=0, then a=2, b=-5 and c=-4.
If you're in to ax+by-c=0, then a=2, b=-5 and c=4.

No problem at all.

ax+by=0 is another matter, though, because there is no c, so there is no way to describe the equation 2x-5y-4=0 with this system.

Answer 3

so in short, the approprite method is ax+by+c=0

Answer 4

also, my doubt is we can or can't write it as ax + by - c = 0 or
ax + by = 0

Answer 5

In short, ax+by+c=0 or ax+by-c=0 doesn't matter much. First is preferred, because it looks neater.

Third is wrong, because it misses out on a group of equations.

Answer 6

Because you have called it linear equations, you can also understand why the third method is wrong: ax+by=0 only represents all lines through the origin. It cannot describe all the other possible lines.

Answer 7

k
@ZeHanz thank you so much

Answer 8

YW!