tolong bantuin dong

1a) m = 1/2 dan melalui ( 0, - 1 )
y - y1 = m (x - x 1)
y - - 1 = 1/2 (x - 0)
y + 1 = 1/2x
y = 1/2x - 1 atau x -2y -1 = 0
b) m = -1, melalui (0, 3)
y - 3 = -1 (x - 0)
y - 3 = -x
y = -x + 3 atau x + y -3 = 0
2a) m = 3/5 , melalui (5, 9 )
y - 9 = 3/5 (x - 5)
y - 9 = 3/5x - 3
y = 3/5x +6 atau 3x -5y +30 = 0
b) m = -1/2, melalui (6, 3)
y - 3 = -1/2 (x - 6)
y - 3 = -1/2x + 3
y = -1/2x + 6 atau x + 2y -12 = 0
3a) garis melalui (-1, -4)(2, 6)
( y - y1)/(y2 - y1) = (x - x1)/(x2 - x1)
(y - -4)/(6- - 4) = (x - - 1)/(2 - - 1)
(y + 4)/(6+4)/(x + 1)/(2+1)
(y + 4)/(10) = (x + 1)/(3)
3(y + 4) = 10(x + 1)
3y + 12 = 10x + 10
10x - 3y -2 = 0
atau 3y = 10x -2
y = (10x -2)/3
y = 10/3x -2/3
b) sama caranya dengan a) silahkan lanjutkan....!