Persamaan garis yang melalui titik (2, -4) dan ( -1, 3) adalah ...
A. 7x + 3y = - 2
B. 2x - 3y = 2
C. 7x - 3y = - 2
D. 7x + 3y = 2![]()
A. 7x + 3y = - 2
B. 2x - 3y = 2
C. 7x - 3y = - 2
D. 7x + 3y = 2
-Persamaan garis lurus-
Rumus persamaan garis lurus yang melalui (x1,y1) dan (x2,y2) adalah :
[tex] \huge \: \frac{y - y1}{y2 - y1} = \frac{x - x1}{x2 - x1} [/tex]
____________________________
(x1,y1) = (2,-4)
(x2,y2) = (-1,3)
[tex] \frac{y - y1}{y2 - y1} = \frac{x - x1}{x2 - x1} [/tex]
[tex] \frac{y - ( - 4)}{3 - ( - 4)} = \frac{x - 2}{( - 1) - 2} [/tex]
[tex] \frac{y + 4}{7} = \frac{x - 2}{ - 3} [/tex]
[tex] - 3(y + 4) = 7(x - 2)[/tex]
[tex] - 3y - 12 = 7x - 14[/tex]
[tex]14 - 12 = 7x + 3y[/tex]
[tex]2 = 7x + 3y[/tex]
[tex]7x + 3y = 2[/tex]
