Tolong kakak kakaknyg bisa Tentukan persamaan garis lurus jika diketahui informasi berikut. a. melalui (1,4) dan (2,-1) b. melalui (-1,0) dan (3,-8) pakai cara

a) melalui (1, 4) dan (2, -1)
x1 = 1
y1 = 4
x2 = 2
y2 = -1

(y - y1) / (y2- y1) = (x - x1) / (x2 - x1)
(y - 4) / (-1 - 4) = (x - 1) / (2 - 1)
(y - 4) / (-5) = (x - 1) / 1
y - 4 = (-5)(x - 1)
y - 4 = -5x + 5
y = -5x + 5 + 4
y = -5x + 9

b) melalui (-1, 0) dan (3, -8)
x1 = -1
y1 = 0
x2 = 3
y2 = -8

(y - y1) / (y2 - y1) = (x - x1) / (x2- x1)
(y - 0) / (-8 - 0) = (x - (-1)) / (3 - (-1))
y / (-8) = (x + 1) / 4
y = (-8)(x + 1) / 4
y = (-2)(x + 1)
y = -2x - 2

upa) (y - y1) / (y2 - y1) = (x - X1) / (x2 - X1)
(y - 4) / (- 1 - 4) = (x - 1) / (2 - 1)
(y - 4) / -5 = (x - 1) / 1
1 (y - 4) = - 5(x - 1)
y - 4 = - 5x + 5
y + 5x = 5 + 4
y + 5x = 9

b) (y - y1) / (y2 - y1) = (x - X1) / (x2 - X1)
(y - 0) / (-8 - 0) = (x + 1) / (3 + 1)
y / - 8 = (x + 1) / 4
4y = - 8(x + 1)
4y = - 8x - 8
4y + 8x = - 8