sumanddifference
Sum and difference refers to two quantities derived from two numbers a and b: the sum s = a + b and the difference d = a − b. The pair (s, d) uniquely determines a and b, since a = (s + d)/2 and b = (s − d)/2. Conversely, s and d are easy to compute from a and b.
Key identities involve these quantities. For example, (a + b)^2 = a^2 + 2ab + b^2 and (a − b)^2 = a^2
Algebraic use includes solving simple linear systems, converting between variables, and factoring. Knowing the sum and
Examples help illustrate the method. If a = 7 and b = 3, then s = 10 and d =
Extensions of the idea appear in broader contexts, including vector and complex-number settings, where analogous sum