Final answer:
The slope of the inequality 4x + 5y < 20 is -4/5, which is determined by rearranging the inequality to the slope-intercept form of a line.
Step-by-step explanation:
To find the slope of the inequality 4x +5y < 20, let's first ignore the inequality part and write the equation in slope-intercept form, which is y = mx + b, where m is the slope and b is the y-intercept.
By rearranging the terms, we get 5y = -4x + 20.
Next, divide each term by 5 to solve for y, yielding y = -4/5x + 4.
Thus, the slope of the line related to this inequality is -4/5x .
Note that the inequality symbol does not affect the slope of the line related to the inequality.