Van thinks that the answer to - 3x < 12 is x < - 4. how will you convince him that his answer is incorrect?

When rearranging an inequality, it is the same as rearranging an equation. However, if you divide or multiple by a negative number, the inequality sign flips. To simply this equation, you have to divide both sides by - 3, which will make the inequality sign flip. Therefore, the answer is actually:

x>-4