Answer:
You would solve this as if the inequality sign was an equal sign.
Just make sure when you divide by a negative or multiply by a negative the sign switches, anyways:
5 + 5(x +4) < 20
Distribute the 5 and simplify
5 + 5x + 20 < 20
25 + 5x < 20
Isolate x (subtract 25 from both sides)
5x < -5
Divide by 5
x < -1
