Option 1: solve the inequality. Add 7 to both sides, and multiply by -3 (don't forget that this makes the inequality switch direction!) to get or x > -9
Option 2. Plug 0 in it. You get -7 < 20, which is obviously true. So 0 is in the set of solution and it means B and C are possible solutions. So let's check another easy value. let's say -10. replacing it you get or . But 23 is obviously greater than 20, which means -10 is not a part of the solution. Correct answer is B