(1, 4), (2, -3) and (-1, -2)
Then the equation of AB is
$\text{y}-\text{y}_=\frac{\text{y}_2-\text{y}_1}{\text{x}_2-\text{x}_1}(\text{x}-\text{x}_1)$
$\text{y}-4=\frac{-3-4}{2-1}(\text{x}-1)$
$\text{y}-4=\frac{-7}{1}(\text{x}-1)$
$\text{7x}+\text{y}=11$
Equation of side BC is
$\text{y}-\text{y}_2=\frac{\text{y}_3-\text{y}_2}{\text{x}_3-\text{x}_2}(\text{x}-\text{x}_2)$
$\text{y}-(-3)=\frac{-2-(-3)}{-1-2}(\text{x}-2)$
$\text{y}+3=\frac{1}{-3}(\text{x}-2)$
$\text{x}+\text{3y}+7=0$
Equation of side AC is
$\text{y}-\text{y}_1=\frac{\text{y}_3-\text{y}_1}{\text{x}_3-\text{x}_1}(\text{x}-\text{x}_1)$
$\text{y}-4=\frac{-2-4}{-1-1}(\text{x}-1)$
$\text{y}-4=3(\text{x}-1)$
$\text{y}-\text{3x}=1$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.