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Algebra real numbers, formulas, linear and quadratic functions, exponent properties, products and factoring

Quadratic Functions

The formula for computing the area of a rectangle is

This formula tells you that the area of a rectangle may be found by multiplying its length by its width. For example, the area of a rectangle 5 inches long and 2 inches wide may be found by substituting '5' for 'L' and '2' for 'W' in the formula and then multiplying:

A = 5 - 2 = 10

Hence the area of the given rectangle is 10 square inches.

If the rectangle is such that the length is the same as the width, the rectangle is called a square, and the formula for its area is

algebra20-310 (1K)

The numeral '2' is called an exponent. The expression 'W2' is a shorthand notation for

W - W

The set of all ordered pairs of real numbers (x, y) such that

y = x2

is a function. Some ordered pairs that belong to this function are:

(0,0) (+1, +1), (-1, +1), (+2, +4), (-2, +4)

The graph of this function is not a line; the function is not a linear function. it is an example of a quadratic function. Its graph is a parabola:

Another example of a quadratic function is the set of all ordered pairs of real numbers (x, y) such that

y = +2x2 + +5x + -1

If 'a', 'b', and 'c' are real numbers, and 'a' <> 0, then the set of all ordered pairs (x, y) such that

y = +ax2 + bx + c

is called a quadratic function. The properties of quadratic functions are studied in analytic geometry and calculus.

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Real Numbers

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Linear Functions

Quadratic Functions

Functions of Higher Degree

Properties of Exponents

Products and Factoring

Quadratic Equations

Solving Problems

Algebra Fundamentals