Section plane is the intersection of a plane cutting through a solid

ambot

single plane method:-

let A and B be the two chosen instument station

Q be the elevate object whose elevation is required

A Band Q lies in the same vertical plane

double plane method:-

let A and B be the not in the same verticale plane as that of elevayed object Q they are in two vertical planes

Tilt of cutting plane is between (perpendicular to axis of the cone) and (parallel to the side of the cone).

Coordinate Plane