One Variable Equations

like terms

"Like terms" are terms whose variables (and their exponents such as the 2 in x2) are the same. In other words, terms that are "like" each other. Note: the coefficients (the numbers you multiply by, such as "5" in 5x) can be different.

constant

A fixed value. In Algebra, a constant is a number on its own, or sometimes a letter such as a, b or c to stand for a fixed number. Example: in "x + 5 = 9", 5 and 9 are constants If it is not a constant it is called a variable.

coefficient

A number used to multiply a variable. Example: 6z means 6 times z, and "z" is a variable, so 6 is a coefficient. Variables with no number have a coefficient of 1. Example: x is really 1x. Sometimes a letter stands in for the number. Example: In ax2 + bx + c, "x" is a variable, and "a" and "b" are coefficients.

variable

A symbol for a number we don't know yet. It is usually a letter like x or y. Example: in x + 2 = 6, x is the variable.

solution

A value we can put in place of a variable (such as x) that makes the equation true. Example: x + 2 = 7 When we put 5 in place of x we get: 5 + 2 = 7 Which is true, so x = 5 is a solution

two-step equation

An equation that needs two steps to solve.

point of intersection

Intersection Where lines cross over (have a common point). The red and blue lines have an intersection.

Distributive Property

The distributive property lets you multiply a sum by multiplying each addend separately and then add the products. OK, that definition is not really all that helpful for most people. It is easier to understand the meaning if you look at the examples below.

exponent

The exponent of a number says how many times to use that number in a multiplication. It is written as a small number to the right and above the base number.

inverse operation

The operation that reverses the effect of another operation. Example: Addition and subtraction are inverse operations. Start with 7, then add 3 we get 10, now subtract 3 and we get back to 7. Another Example: Multiplication and division are inverse operations.