Question

What is diagonals, opposite vertices and opposite side in a abcd square?

Answer 1

AC and BD are diagnols. c, a and d, b are the opposite vertices.
Ab and dc, as and bc are opposite sides....

Answer 2

Diagonals are the segments in the square joining the opposite vertices.

So for squareABCD the diagonals will be AC and BD

opposite vertices are the Diagonally Opposite corners of the square

So for square ABCD the vertex Opposite to A will be C and for B opposite vertex will be D

Opposite sides in square ABCD will be AB opposite to CD and AD will be opposite to BC

Also keep in mind that 4 vertices of any quadrilateral will be named in adjacent order of vertices