The intercept form is y = mx + b and in terms of inequalities it would be
y (<, >, ≤, ≥)
You need to bring 6x to the other side of the inequality to make it into the intercept form...
6x - 4y < 20
6x - 6x - 4y < 20 - 6x
-4y < 20 - 6x
Divide both sides by -4 to isolate y. Since you are dividing by a negative coefficient you need to switch the direction that the inequality to pointing to.
y > -5 + 6/4
or more simplified ..
y > -5 + 2/3
