Final answer:
In the expression 9m + 3n + 4a, the number 9 is the coefficient of the variable 'm'. It indicates how many times 'm' is counted in the expression. Coefficients are the numerical factors that multiply variables in algebraic expressions.
Step-by-step explanation:
In the expression 9m + 3n + 4a, the number 9 is best described as a coefficient. It is the numerical factor that multiplies the variable 'm'. In an algebraic expression, coefficients are the numbers that stand in front of variables, displaying how many times that variable is being counted. For example, in the standard form of a linear equation y = mx + b, the coefficient 'm' represents the slope of the line, and 'b' represents the y-intercept. In the equation y = 9 + 3x, 3 is the coefficient (slope), and 9 is the constant term (y-intercept).
Additionally, in the context of a quadratic equation, such as at² + bt + c = 0, 'a', 'b', and 'c' are coefficients to their respective terms with 'a' being the coefficient to the quadratic term t², 'b' to the linear term t, and 'c' as the constant term.