Question

How to graph the inequality on a plane.
4x+5y≤20?

Answer 1

First plot the line 4x+5y=20


Then test the point (0,0). You do this by plugging in x=0 and y=0 into 4x+5y≤20 and seeing if the simplified result is true. If so, then (0,0) is in the solution set, which means that it's in the shaded region. If not, then (0,0) is NOT in the solution set and NOT in the shaded region.