Final answer:
The equation of the plane that passes through the point (3,6,9) and is parallel to the yz-plane is x = 3.
Step-by-step explanation:
The student asks for the equation of the plane passing through the point (3,6,9) and parallel to the yz-plane. To find the equation of such a plane, we need to recognize that being parallel to the yz-plane implies the plane will have a constant x-value. Planes are usually expressed in the form ax + by + cz + d = 0. Since the plane is parallel to the yz-plane, it does not vary as y or z changes, indicating that a = 1 and b = c = 0. Therefore, the general equation of the plane becomes x + d = 0. To find 'd', we plug the x-coordinate of the given point into the equation, which gives us 3 + d = 0, hence d = -3.
So, the final equation of the plane is x = 3.