Question

Equation of plane parallel to z-axis.

• A. $ax+by+d=0$
• B. $bx+cz+d=0$
• C. $by+cz+d=0$
• D. None of these

Answer 1

The correct option is A $ax+by+d=0$

Any line in the x-y plane, which can be written as $ax+by+c=0$, would be perpendicular to z axis.

Since the equation of a plane has the direction ratio of its normal as its coefficients, the plane equation can be written as $ax+by+d=0$