Question

determine a equaçao reduzida da reta que passa pelos pontos A(2, -1) e B(-1,1)

Answer 1

m=ya-yb/xa-xb= -1-1/2+1= -2/3

y-yb= m.(x-xb)

y-1 = -2/3.(x+1)

3.(y-1)= -2.(x+1)

3y-3 = -2x-2

3y = -2x+1 ===> : (3)

y = (-2/3)x + 1/3

Answer 2

Resposta:

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

Explicação passo-a-passo:

$a = \frac{y - y.}{x - x.}$

a = 1 - ( - 1) / - 1 - 2

a = 1 + 1 / - 3

a = - 2/3

y - y. = a(x - x.)

y - (-1) = -2/3(x - 2)

y + 1 = -2/3x + 2/3•2

y = - 2/3x + 4/3 - 1

y = -2/3x + 1/3