You typed an equation, not an inequality.
(Equations contain an equal sign; inequalities contain an inequality symbol.)
y = -(2/3)x - 12
This is the equation of a line.
There are many different forms in which we could write the equation for this particular line, but you typed it in what we call "slope-intercept" form.
Slope-intercept form is when the equation for a line is solved for y (i.e., the variable y is all by itself on one side of the equal sign, and everything else is on the other side).
Here is the generic slope-intercept form, using the symbol m to represent the line's slope and the symbol b to represent the line's y-intercept:
y = mx + b
We call this form "slope-intercept" because it shows both the slope (the value m) and the y-intercept (the value b).
If you inspect and compare the following two equations, then can you tell for the second equation which number is m and which number is b?
y = mx + b
y = -(2/3)x - 12
If you can, then you've answered this exercise.