tolong dong... mendadak soalnya nih

saya kurang tahu tahu tahu

jawab
m = (y2-y1)/(x2-x1)
y = m(x -x1) + y1

a) (2,2) , (4,2)
m  = (2-2)/(4-2) = 0
y - 2 = 0(x - 1)
y - 2 = 0
y = 2

b) (3,-1) ,(9,-1)
m = (-1 + 1)/(9-3) = 0
y + 1 = 0(x - 3)
y = - 1

c) (0,0) ,(4,4)
m = (4-0/(4-0) = 1
y - 0 = 1( x - 0)
y = x

d)  (3,4) , (3,5)
garis x = 3

e. (-2,- 3), (-2,7)
garis x = -2