Which term describes a mathematical phrase that contains numbers, operations, and/or variables?

The correct term that describes a mathematical phrase containing numbers, operations, and/or variables is an expression. A mathematical expression is composed of various terms combined using operations such as addition, subtraction, multiplication, and division. Expressions could be as simple as a single number or variable, or more complex, incorporating multiple numbers and variables along with operations.

Equations, on the other hand, are a special type of expression that shows the equality between two expressions using an equals sign. Coefficients refer specifically to the numerical factor in front of a variable, such as in the expression (3x), where 3 is the coefficient of (x). Constants are fixed values that do not change, like the number 5 in an expression. Thus, the most accurate term for a mathematical phrase that includes numbers and/or variables with operations is an expression.