ACT Practice Question: Lines in Coordinate Plane

 
Here is a practice question on straight lines in the coordinate plane.

If the point $(a, -2)$ falls on the straight line $2y-3x=-6$ in the standard $(x, y)$ coordinate plane, then $a=$ ?

1. $\quad -\dfrac{3}{2}$
2. $\quad -\dfrac{2}{3}$
3. $\quad \dfrac{2}{3}$
4. $\quad \dfrac{3}{2}$
5. $\quad \dfrac{10}{3}$