Mapel : Matematika

Kelas : VIII

Bab : 4 - Persamaan Garis Lurus

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Bagian A

2y - 3x = 12

m = -a/b

a = koefisien x

b = koefisien y

m = - (-3)/2

m = 3/2

(2,5) → x1 = 2 , y1 = 5

karena sejajar maka gradiennya pun Sama = 3/2

y - y1 = m(x - x1)

y - 5 = 3/2(x - 2)

y - 5 = 3/2x - 6/2

y = 3/2x - 6/2 + 5

y = 3/2x - 6/2 + 10/2

y = 3/2x + 4/2

y = 3/2x + 2 ✔️

Bagian B

3y+4x-12=0

m = -a/b

a = koefisien x

b = koefisien y

m = -4/3

(-4,6) → x1 = -4 , y1 = 6

karena tegak lurus maka :

m1 × m2 = -1

-4/3 × m2 = -1

m2 = -1 ÷ -4/3

m2 = -1 × -3/4

m2 = 3/4

y - y1 = m(x - x1)

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

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

y - 6 = 3/4x + 12/4

y = 3/4x + 12/4 + 6

y = 3/4x + 12/4 + 24/4

y = 3/4x + 36/4

y = 3/4x + 9 ✔️