Question

Considere os pontos A(-2, 1) e B(1, 2). Determine a equação geral da reta.​

Answer 1

$\large\boxed{\begin{array}{l}\begin{vmatrix} \sf-2&\sf1&\sf1\\\sf1&\sf2&\sf1\\\sf x&\sf y&\sf1\end{vmatrix}=0\\\sf-2(2-y)-1(1-x) +1(y-2x)=0\\\sf -4+2y-1+x+y-2x=0\\\sf -x+3y-5=0\cdot(-1)\\\sf x-3y+5=0\end{array}}$