Vertex O is the origin.

Therefore, its coordinates are (0,0).

Vertex A is on the Y – axis.

Therefore its X coordinate = 0.

Line joining vertex A and (4,3) in parallel to X – axis, therefore its y coordinate will remain constant. Since point A is on the line, its Y coordinate = 3

Therefore coordinates of vertex A are(0,3)

Vertex B is on X – axis.

Therefore it's Y coordinate = 0.

Line joining vertex B and (4,3) in parallel to Y – axis, therefore its x coordinate will remain constant. Since point A is on the line, its x coordinate = 4

Therefore coordinates of vertex A are(4,0)

Hence, the coordinate of the other three vertices of the given rectangle is (0,0),(0,3) and (4,0).