29. In the equation f(t) = 4t + 9, which of the following is the independent variable?
Answer: B
The independent variable in the equation f(t) = 4t + 9 is t.
In the equation f(t) = 4t + 9, the independent variable is represented by the symbol t, as it is the variable that can be manipulated or changed, affecting the outcome of the function.
A) f
The symbol f represents the function itself, not an independent variable. It is dependent on the value of t, which means that f changes as t changes.
B) t
This option is correct as t is the independent variable in the equation. It is the variable that can take on different values, and the function f(t) is calculated based on the value of t.
C) 4
The number 4 is a constant coefficient in the equation and does not vary. It is part of the function but does not serve as an independent variable since it does not change or impact the outcome of the function.
D) 9
Similar to option C, the number 9 is also a constant in the equation. It acts as a fixed value added to the product of 4 and t, but it does not represent an independent variable.
Conclusion
The correct answer is B, as t is the independent variable that can vary, influencing the output of the function f(t). Options A, C, and D do not represent independent variables; instead, they are either the result of the function or constants that do not change with respect to the independent variable.