Two lines whose direction ratios are a1, b1, c1 and a2, b2, c2 are perpendicular, if
Unique point is obtained for the pair of equations a1x + b1y + c1 = 0 and a2x +b2y + c2 = 0 if
Parallel lines are obtained for the pair of equations a1x+b1y+c1=0 and a2x+b2y+c2=0 if
What can you tell about the ratio of coefficients of the lines a1x + b1y + c1 = 0 and a2x + b2y + c2 = 0 from the graph ?