Question

a student claims than inequality 3x + 1 is greater than 0 is always true because multiplying a number by 3 and then adding 1/2 a result always produces a number greater than zero

Answer 1

Greetings!

This is not correct because if the x was any negative more than 1, it would always return an answer in the negatives:

x = -2

3(-2) + 1 = -5

x = -1

3(-1) + 1 = -2

So the student is wrong, because it is not always true, it is only greater than 0 when the x is bigger than a third.

Hope this helps!