Question

a equacao da reta que passa pelos pontos P(3,1) e T(2,-1)

Answer 1

a = y2 - y1
      x2 - x1 

a = - 1 - 1 ==> a = - 2 ==> a = 2
       2 - 3                - 1
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y = ax + b        ( (3,1)  ; a = 2

2.3 + b = 1 ==> b = 1 - 6 ==> b = - 5
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y = ax + b ==> y = 2x - 5