4y

4y is an algebraic expression formed by multiplying the constant 4 by the variable y. It is a monomial of degree 1 and has coefficient 4. The expression is homogeneous: scaling y by a factor scales 4y by the same factor. In fields where arithmetic is defined (such as the real or complex numbers), y can be a real or complex number; in vector spaces, 4y denotes scalar multiplication of a vector by the scalar 4.

Evaluation and examples: if y=7, then 4y=28; if y=-3, then 4y=-12; if y=0, then 4y=0. If y is a more general object that supports scalar multiplication (like a matrix or a vector), 4y multiplies every component by 4. In algebra, 4y can be part of larger expressions or equations; for example, in 4y + 3 = 11, solving yields y=2. It can be factored from terms with a common factor 4, as in 4(y1 + y2) if y represents a sum y1 + y2. It is also used to express proportional relationships and linear functions, where y varies linearly with some other variable.

Notation: the letter y is a placeholder, and 4 is a constant multiplier; the concept generalizes to any nonzero scalar c, with cy representing a scalar multiple of y.