Question

please any one prove 11th question

Answer 1

Basic property of parellogram is opposite sides are parallel.

So first basically given AX//Cy
These are joined to one side of parellogram of equal and parellel sides.

Ax=Cy
And AX//Cy

So AXCY is parallelogram

Answer 2

(1) congruent the triangle Ayc and Acx
by doing this,
AX=YC
(2) AX =YC
Ax//YC
SO ,AXCY is //gm