A weighing scale, balance, or seesaw is often presented as an analogy to an equation. Each side of the balance corresponds to one side of the equation. Different quantities can be placed on each side: if the weights on the two sides are equal the scale balances, corresponding to an equality represented by an equation; if not, then the lack of balance corresponds to an inequality represented by an inequation. In the illustration, x, y and z are all different quantities (in this case real numbers) represented as circular weights, and each of x, y, and z has a different weight. Addition corresponds to adding weight, while subtraction corresponds to removing weight from what is already there. When equality holds, the total weight on each side is the same. |

About us|Jobs|Help|Disclaimer|Advertising services|Contact us|Sign in|Website map|Search|
**
**

GMT+8, 2015-9-11 21:59 , Processed in 0.142525 second(s), 16 queries .