Question

ABO2) Determine a equação geral da
reta sabendo que os pontos A(2, 1) e
B(-2, 4) pertencem a reta. *​

Answer 1

x....y....1

2....1....1

-2...4....1

x-2y+8+2-2y-4x = 0

-2y-2y = 4x-x-8-2

-4y = 3x-10

4y = -3x+10

y = (-3x+10)/4 ou

y = -3x/4 + 10/4

y = -3x/4 + 5/2

Answer 2

$\boxed{\begin{array} {l} \begin{vmatrix}\sf2&\sf1&\sf1\\\sf-2&\sf4&\sf1\\\sf x&\sf y&\sf1\end{vmatrix}=0\\\sf2\cdot(4-y)-1\cdot(-2-x)+1\cdot(-2y-4x)=0\\\sf8-2y+2+x-2y-4x=0\\\sf -3x-4y+10=0\cdot(-1)\\\sf 3x+4y-10=0\end{array}}$