Question

escreva a equaçao reduzida  da reta r que passa pelos pontos A(-1,0) e B (2,-1),Indique os coeficientes angular e linear dessa reta

Answer 1

$\left[\begin{array}{ccc}x&y&1\\x_a&y_a&1\\x_b&y_b&1\end{array}\right]$

Fazendo o Determinante temos:

$\left[\begin{array}{ccc}x&y&1\\-1&0&1\\2&-1&1\end{array}\right] \begin{array}{ccc}x&y&\\-1&0&\\2&-1&\end{array}\right]$

$0+x+y+0+2y+1=0$
$3y=-x-1$
$y= \frac{-x-1}{3}$ ou $y= \frac{-x}{3} - \frac{1}{3}$

Coeficiente Angular: $\frac{-1}{3}$
Coeficiente Linear: $\frac{-1}{3}$