Question

The condition for `ax^2 +2cxy+by^2 +2bx+2ay+c` is resolvable into two linear factors is

Answer 1

`ax^2+2hxy+by^2+2yx+2fy+c=0`
`/_=abc+2fgh-af^2-bg^2-ch^2=0`
`=abc+2abc-a^3-b^3-c^3=0`
`=a^3+b3+c^3=3abc`.