Jawabanmu

2014-07-06T16:01:36+07:00
Gradien garis:
m = (y2-y1)/(x2-x1) = (-1-3)/(4-2) = -4/2 = -2

Persamaan garis:
y-y1 = m(x-x1)
y-3 = -2(x-2)
y = -2x+4+3
y = -2x+7

Mencari k:
y = -2x+7
k = -2(1)+7
k = -2+7 = 5