50 point nih...tolongin yak:v

Bab Persamaan Garis
Matematika SMP Kelas VIII

1a] m = y/x
          = 6/3
          = 2

1b] m = y/x
          = -4/2
          = -2

2a] y = mx + c

      2y = 4x - 6
      2y/2 = (4x - 6)/2
      y = 2x - 3

    m = 2

2b] 2x - 4y = 8
      2x - 8 = 4y
      4y/4 = (2x - 8)/4
      y = (1/2) x - 2

      m = 1/2

3] a dan b
    m = (y2 - y1) / (x2 - x1)
        = (8 - 6) / (2 - 3)
        = 2/-1
        = -2

  c dan d
   m = (y2 - y1) / (x2 - x1)
       = (-2 - 2) / (4 - 8)
       = -4/-4
       = 1

4] y = m (x - x1) + y1
    y = 2 (x - 3) + 4
    y = 2x - 6 + 4
    y = 2x - 2

5] (y - y1) / (y2 - y1) = (x - x1) / (x2 - x1)
    (y - 4) / (-6 - 4) = (x - 3) / (2 - 3) 
    (y - 4)/-10 = (x - 3) / -1
    y - 4 = 10 (x - 3)
    y - 4 = 10x - 30
    y = 10x - 30 + 4
    y = 10x - 26

1. A (3,6)
m = y/x

m = 6/3 = 2

B (2,-4)

m = y/x

m = -4/2

m = -2

2. 2y = 4x-6

y = 2x -3

m = 2

2x-4y = 8

2x-8 = 4y

1/2 x -2 = y

m = 1/2

3.A (3,6) B (2,8)

m = (y2-y1)/(x2-x1)

= (8-6)/(2-3)

= 2/(-1)

m= -2

C (8,2) D (4,-2)

m = (y2-y1) /(x2-x1)

m = (-2-2)/(4-8)

m = -4/-4

m = 1

4. Pers garis A (3,4) m =2

(y-y1) = m (x-x1)

(y-4) = 2 (x-3)

y-4 = 2x -6

y = 2x - 2

Atau

2x-y = 2

5. Persamaan garis melalui A (3,4) B (2,-6)

(y-y1)/ (y2-y1) = (x-x1)/(x2-x1)

(y-4)/(-6-4) = (x-3)/(2-3)

(y-4)/(-10) = (x-3)/(-1)

-y+ 4 = -10x + 30

10x -y = 26