Explainer — Resource Type Pages

Factoring in Algebra

Factoring rewrites an expression as a product of simpler factors. It is the reverse of expansion. Factoring exposes multiplicative structure that can make equations easier to solve and…

Systems of Linear Equations

A system of linear equations asks for values that satisfy two or more linear equations at the same time. For two variables, a solution is an ordered pair…

Linear Equations

A linear equation in one variable can be written as ax+b=cax+b=c, where aa, bb and cc are constants and a≠0a\ne0. Solving means finding every input that makes the…

Linear Inequalities

A linear inequality compares two expressions using <<, >>, ≤\le or ≥\ge. Its solution is usually a set of values rather than a single number. Most equation-solving operations…

Like Terms and Simplifying Expressions

Simplifying an algebraic expression means rewriting it in an equivalent form that is easier to read or use. One of the first tools is combining like terms: terms…

Expressions and Algebraic Expressions

An expression represents a mathematical value. It can contain numbers, variables, operations, powers and grouping symbols, but it does not state that two quantities are equal. Algebraic expressions…

Properties of Algebraic Operations

The properties of algebraic operations explain when we can rearrange, group or expand expressions without changing their value. They are the reasons a line of algebra follows from…

Algebraic Identities

An algebraic identity is an equation that is true for every permitted value of its variables. For example, 2(x+3)=2x+62(x+3)=2x+6 holds whatever real number replaces xx. It gives two…

Coefficient

A coefficient is a factor multiplying a specified variable or variable part. In 7x7x, the numerical coefficient is 77. In −3×2-3x^2, it is −3-3, including the negative sign.…

Polynomials

A polynomial is a finite sum of terms made from coefficients and variables raised to non-negative integer powers. In one variable, examples include 4x+14x+1, x2−5x+6x^2-5x+6 and 77. The…

Variable in Maths

A variable is a symbol that represents a value. It can stand for an unknown number, a quantity that changes, or an arbitrary number in a general rule.…

A percentage expresses a quantity in relation to 100. The word percent means “per hundred,” so 25%=25100=14=0.25. 25\%=\frac{25}{100}=\frac14=0.25. Percentages are useful because they create a common scale for…