Since, article is every time allocate in front line of the mirror therefore the sign of article is get hold of as negative.

Since, the middle of curvature and focus lie down in forepart of the concave mirror, so indication of radius of curvature and focal length are grasp as negative in the instance of concave mirror.

When image is set up in forepart of the mirror, the length of image is taken as negative and when figure is formed beyond the mirror, the space of image is taken as positive.

High point of image is taken as positive in the occurrence of erect persona and extract as negative in the sample of inverted figure.

The Sign convention in the case of a convex mirror:

Since, article is always located in frontline of the mirror therefore the signal of object is meant to be negative.

Since, the middle of curvature and focus recline behind the convex mirror, so signal of radius of curvature and focal length are meant to be positive in the sample of convex mirror.

In the situation of convex mirror, figure is always devised behind the mirror, thus the space of image is taken as positive in sign.

In the case of a convex mirror, all the time an erect image is established, thus the high point of figure is taken as positive.

All widths on the apex axis are measured from the optical middle.

The distances calculated in the way of incident rays are always positive and all the gaps measured in the way opposite to that of the incident rays are always negative.

All distances calculated over the main axis are positive. So, height of an article and that of an erect figure are positive and all distances measured downwards to the main axis are negative