Jawabanmu

2014-02-06T23:08:08+07:00
M = -a/b
m = -1/-2 = 1/2
karena m tegak lurus jadi, m1 x m = -1
1/2 x m = -1
m = -1 x 2/1
= -2/1
y-y1=m (x-x1)
y - 7 = -2/1 (x-1)
y-7 = -2x +2
y = -2x +2 +7
y = -2x +9