Define symmetry and proportion. why are they important to artistic design?

Whenever you design something, it is important to include equality and quantity to the design if you want it to look right. Imagine designing a building; you must proportion the design correctly and be sure that the symmetry is correct or the building may appear lop-sided, out of shape, or could potentially tear down over a period of time. The same applies to art.

The term collage was coined by both  georges braque  and  pablo picasso  in the beginning of the 20th century when collage became a distinctive part of modern art.hope this sorry if there wasn't more of an explanation!