1 Cubism was invented around 1907 in Paris by Pablo Picasso and Georges Braque. 2  Cubism was the first abstract style of modern art. 3  A Cubist painting ignores the traditions of perspective drawing and shows you many views of a subject at one time. 4  The Cubists introduced collage into painting.
Two linear systems using the same set of variables are equivalent if each of the equations in the second system can be derived algebraically from the equations in the first system, and vice versa.
The equivalent of a substance is the amount of the substance multiplied by its valence. The equivalent could be also formally defined through the amount of substance which will either: 1  react with or supply one mole of hydrogen ions (H +) in an acidâbase reaction; or.2  react with or supply one mole of electrons in a redox reaction.he equivalent could be also formally defined through the amount of substance which will either: 1  react with or supply one mole of hydrogen ions (H +) in an acidâbase reaction; or.