1. Tentukan persamaan garis yang melalui pasangan-pasangan titik berikut (a). A(3,5) dan B(7,11) (b). C(6,0) dan D(0,-8)

 a.) [tex] \frac{y-y1}{y2-y1} = \frac{x-x1}{x2-x1} [/tex]
     [tex] \frac{y-5}{11-5} = \frac{x-3}{7-3} [/tex]
     [tex] \frac{y-5}{6} = \frac{x-3}{4} [/tex]
     4.(y-5) = 6.(x-3)
     4y-20 = 6x-18
     4y = 6x -18 +20
     4y = 6x +2
     y  = [tex] \frac{3}{2} x + \frac{1}{2} [/tex]

b.) [tex] \frac{y-y1}{y2-y1} = \frac{x-x1}{x2-x1} [/tex]
    [tex] \frac{y-0}{-8-0} = \frac{x-6}{0-6} [/tex]
    [tex] \frac{y-0}{-8} = \frac{x-6}{-6} [/tex]
    -8.(x-6) = -6.(y-0)
    -8x + 48 = -6y+0
    8x-48 = 6y
    6y = 8x-48
    y = [tex] \frac{4}{3} [/tex] x - 8

maaf kalau salah