Answer
perpendicular
Work Step by Step
Using $y=mx+b$, where $m$ is the slope, the slope of $
y=\dfrac{3}{4}x+1
$ is
\begin{array}{l}
m_1=\dfrac{3}{4}
\end{array}
and the slope of $y=-\dfrac{4}{3}x+1$ is
\begin{array}{l}
m_2=-\dfrac{4}{3}
.\end{array}
Since $m_1\cdot m_2=-1,$ then the given lines are $\text{
perpendicular
.}$