s is dependent; t is independent
Work Step by Step
Given that $s=3t^2+5t-1$, s is the dependent variable and t is the independent variable. With this type of equation you are being asked to solve for s based on varying values of t. Because the value substituted for t can be changed arbitrarily, t is called the independent variable. Because the value that is computed for s changes based on the value of t, s is called the dependent variable.