Answer:
Step-by-step explanation:
Solve the inequality 5x − 4y > 20 for y, as follows: Subtract 5x from both sides, obtaining:
-4y > 20 - 5x;
Then divide all terms by -4:
y < -5 +(5/4)x, where the direction of the inequality sign has been reversed because of division by a negative quantity.
Temporarily replace the < symbol with = obtaining y = -5 +(5/4)x. Now choose at least three x values and find the corresponding y values. For example:
x y = -5 +(5/4)x
0 -5
4 0
-8 -15
Now plot these three points (0, -5), (4, 0) and (-8, -15). Draw a dashed line through them. Because of the < symbol in y < -5 +(5/4)x, shade the area underneath the dashed line.