The distance of the object from the mirror line should equal the distance of the image from the mirror line.
the measure of a straight-line distance between two points is called length.
Two points in a plane.
On a flat plane, it is a straight line.
centimeters
It is the distance between its endpoints and there are 180 degrees on a straight line
It is the distance between the end points
The distance between its end points
By unit of length and distance and conversion ,we can say that yes ,a line can be measured by ruler or scale.
The locus of points at a given distance to a line would be a line parallel to the first line. Assuming that both lines are straight.
It depends what you mean by a plane inch. If you mean an inch length on a plane surface, the conversion is 1 to 1 so that 24.6 inch is 24.6 plane inches. If, instead, you mean the measure of an area in a plane, the answer is that there is no equivalence. An inch is a measure of length or distance while according to the above definition, a plane inch is a measure of area. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid without some addition information.
Surveying terminology. The measure of distance along a slope. The distance of a line where elevation changes from point 1 to point 2