Graph of an inequality
Step 1: limit line
In order to graph an inequality we first graph its limit line. We find its limit line equation just by replacing the inequality symbol by "=":
The limit line of the following inequality
-4x + y ≥ 8
is
-4x + y = 8
We find two points: when x = 0 and when y = 0
When x = 0
we replace x by 0 in the equation so we can find y:
-4x + y = 8
↓
-4 · 0 + y = 8
↓
o + y = 8
↓
y = 8
Then, when x=0, then y = 0. Therefore the first point is (0, 8)
When y = 0
we replace y by 0 in the equation so we can find x:
-4x + y = 8
↓
-4x + 0 = 8
↓
-4x = 8
↓
