When you state the coordinate of a point, the abscissa ( coordinate) precedes the ordinate ( coordinate).

Co-ordinate of origin is

Co-ordinate of a point of

Co-ordinate of a point of

Reflection:

When any object is placed in front of a mirror, its image is formed at the same distance behind the mirror as the object is front of it.

Here also

Reflection in line In the adjoining diagram, you see that point reflection is . The does not change, only the changes. become when reflected on .

In a generic form, we can say that the reflection of on is .

Reflection in line

Similarly, you see that point reflection is . The does not change, only the changes. become when reflected on .

In a generic form, we can say that the reflection of on is

Reflection in the origin:

In the above diagram, you would see that in reflection in Origin, both and change. become when reflected in the origin.

Invariant Point:

Any point that remains unaltered under a given transformation is called invariant. For example:

Reflection of in would remain same as

Reflection of in would remain same as

Reflection of in would remain same as

Remember, in case of an Invariant point, the point itself is its own image. Similarly, every point in a like is reflected in itself , the point is invariant.