Slope of a Parametric Curve

The position of a particle moving in the $xy$-plane for time $t \geq 0$ is given by the parametric equations $x = \ln(t + 1)$ and $y = kt^2$, where $k$ is a positive constant. The slope of the line tangent to the particle’s path at $t = 3$ is $8$. What is the value of $k$?