Try the following SAT math practice question (No Calculator, Grid in question) that tests your understanding of properties of straight lines in the coordinate plane.
In the $xy-$plane, the line with equation $y = 6 \; – \; \dfrac{3}{4}x$ intersects the $x-$axis and $y-$axis at the points $M$ and $N$, respectively. What is the length of line segment $\overline{MN}$?