Let $A\left(x_{1}=x, y_{1}=y\right), B\left(x_{2}=-5, y_{2}=7\right)$ and $C\left(x_{3}=-4, y_{3}=5\right)$ be the given points The given points are collinear if

$\mathrm{x}_{1}\left(\mathrm{y}_{2}-\mathrm{y}_{3}\right)+\mathrm{x}_{2}\left(\mathrm{y}_{3}-\mathrm{y}_{1}\right)+\mathrm{x}_{3}\left(\mathrm{y}_{1}-\mathrm{y}_{2}\right)=0$

$\Rightarrow x(7-5)+(-5)(5-y)+(-4)(y-7)=0$

$\Rightarrow 7 \mathrm{x}-5 \mathrm{x}-25+5 \mathrm{y}-4 \mathrm{y}+28=0$

$\Rightarrow 2 \mathrm{x}+\mathrm{y}+3=0$

Therefore, the required relation is $2 \mathrm{x}+\mathrm{y}+3=0$