Penjelasan dengan langkah-langkah:

(1) Garis AB

Gunakan rumus persamaan garis lurus melalui 2 titik.

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

Maka :

A (-1, 4) (x1, y1)

B (-3, 6) (x2, y2)

Sehingga :

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

(y - 4)/6 - 4 = (x - (-1))/(-3) - (-1)

(y - 4)/2 = (x + 1)/(-2)

(-2)(y - 4) = 2(x + 1)

-2y + 8 = 2x + 2

8 - 2 = 2x + 2y

6 = 2x + 2y

-3 ≤ x ≤ -1

4 ≤ y ≤ 6

(2) Garis BC

B (-3, 6) (x1, y1)

C (1, -2) (x2, y2)

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

(y - 6)/(-2) - 6 = (x - (-3))/1 - (-3)

(y - 6)/(-8) = (x + 3)/4

4(y - 6) = (-8)(x + 3)

4y - 24 = -8x - 24

8x + 4y = - 24 + 24

8x + 4y = 0

-3 ≤ x ≤ 1

6 ≤ y ≤ -2

(3) Garis AC

A (-1, 4) (x1, y1)

C (1, -2) (x2, y2)

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

(y - 4)/(-2) - 4 = (x - (-1))/1 - (-1)

(y - 4)/(-6) = (x + 1)/2

2(y - 4) = (-6)(x + 1)

2y - 8 = -6x - 6

6x + 2y = - 6 + 8

6x + 2y = 2

-1 ≤ x ≤ 1

4 ≤ y ≤ -2

Jadi, hasilnya :

(1) Garis AB

2x + 2y = 6

-3 ≤ x ≤ -1

4 ≤ y ≤ 6

(2) Garis BC

8x + 4y = 0

-3 ≤ x ≤ 1

6 ≤ y ≤ -2

(3) Garis AC

6x + 2y = 2

-1 ≤ x ≤ 1

4 ≤ y ≤ -2

Untuk gambar-nya, sudah saya lampirkan ya.

Garis hitam (2x + 2y = 6)

Garis ungu (8x + 4y = 0)

Garis biru (6x + 2y = 2)

Semoga membantu.