LINEAR

In Geometry, a linear problem is one that is solved breadth."by the intersection of two straight lines, or by an equation of the first degree, and which, consequently, admits only of a single solution. Linear Equations, in the Integral Calculus, are those in which the unknown quantity is only of the first degree Thus A x + B =; O is a linear equation, if A and B are not functions of a;; and A d y -f- B y -4- C = O is also a linear equation, when A, B, and C do not contain y. Linear Perspective is that which regards only the positions, magnitudes, and forms of the objects delineated; as distinguished from aerial perspective, in which the variations of the light, colour, and shade of objects, according to their different distances and the quantity of light that falls on them, are also considered and represented. [s. 686]