Basically,
a, b, c, d : constant
x, y, z, d : arbitary
ax + by + cz + d = 0
If we has 3sete of ( x, y, z ), we could the above formula.
And,
a + bx + c + d = ax + 2c
if we found the above, we solved it lke the following:
a = b
a + c + d = 2c -> a - c + d = 0 -> b - c + d = 0
a + bx + c + d = ax + 2c -> ( a - b )*x - a + c - d = 0
so, ( a - b) looks interesting.
And, we could remove all base-numbers in formula.
fractions/ base-number
1/(a+b) = c/a + d/b
so, the above bold looks interesting.
