question_answer 1)

The planes 2x ? y + 4z = 5 and 5x ? 2.5y + 10z = 6 are (a)   perpendicular (b) parallel (c) intersects along y-axis (d) passes through  

Answer:

On comparing given planes with a1x + b1y + c1z = d1 and a2x + b2y + c2z = d2. We get             a2 = 2, b1 = ?1, c1= 4       and a2 = 5, b2 = ?2.5, c2 = 10       Here             Clearly       given planes are parallel. So (b) correct.