Question

Find the equations to the sides of the triangles the coordinates of whose angular points are respectively
$(0,1),(2,0)$, and $(-1,-2)$.

Answer 1

Slope (m) = $\frac{y_2-y_1}{x_2-x_1}$

Equation formed by the side having endpoints $(0,1)$ and $(2,0)$ is obtained as

slope is $m=\frac{0-1}{2-0}=\frac{-1}{2}$

Equation is $y-1=\frac{-1}{2}(x-0)\Rightarrow 2y+x=2$

Similarly for remaining sides with endpoints $(2,0)$, $(-1,-2)$ and $(-1,-2)$, $(0,1)$ are

$3y=2x-4$ and $y=3x+1$ are the remaining two equations of sides of a triangle.