A student claims that the inequality #3x+ 1 >0# is always true because multiplying a number by 3 and then adding 1 to the result always produces a number greater than 0. What is the student's error?

1 Answer
Oct 7, 2017

See explanation.

Explanation:

The student assumes that the number #x# must be positive. For a positive number #x# it is true.

If we multiply a posiitive number by #3# and add #1# to the sum, the result will be positive.