G/s đt (d) luôn đi qua điểm M($x_{M}$ ;$y_{M}$) cđ ∀m
Khi đó: m$x_{M}$ + (2-3m)$y_{M}$ +m-1 =0 ∀m
⇔ m( $x_{M}$ - 3$y_{M}$+1) + 2$y_{M}$ -1=0 ∀m
⇔ $\left \{ {{x_{M} - 3y_{M}+1=0} \atop {2y_{M} -1=0}} \right.$
⇔$\left \{ {{x_{M}=\frac{1}{2}} \atop {y_{M}=\frac{1}{2}}} \right.$ ⇒ M($\frac{1}{2}$ ; $\frac{1}{2}$)