Question

Sa se determine ecuatia dreptei care trece prin punctele A(2,-1) si B(1,-2)​

Answer 1

Răspuns:

Ecuatia  dreptei

(y-yA)/(yB-yA)=(x-xA)/(xB-xA)

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

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

y+1=x-2

y=x-2-1

y=x-3

Explicație pas cu pas:

Answer 2

$\it AB:\ \ \dfrac{x-x_A}{x_B-x_A}=\dfrac{y-y_A}{y_B-y_A} \Rightarrow \dfrac{x-2}{1-2}=\dfrac{y+1}{-2+1} \Rightarrow 2-x=-y-1 \Rightarrow \\ \\ \\ \Rightarrow x-y-3=0$