a symbol (usually a letter like x or y) that represents a number or value in a mathematical expression or equation. Variables are used to represent unknown values or quantities that can change.

the variable that depends on the value of the independent variable. It is the "output" of the function or equation. Its value changes based on the value of the independent variable.

describes how one quantity changes in relation to another. It is often used to describe the slope of a line.

a linear equation that is written as y=mx+b

a rule that takes an input, does something to it, and gives back exactly one output. In other words, for every input, there is one and only one output.

the starting point or value of something, often where a situation begins or where a line crosses the y-axis

the variable that you can change or control. It is the "input" of a function or equation. In many real-world problems, it’s the quantity that causes changes in another quantity.