Question

Find the student’s error in solving the following inequality. 31 < –5x + 6 25 < –5x –5 < x

Answer 1

Answer:

He subtracted -5 from both sides, not -6

Step-by-step explanation:

The inequality that we have to solve in this problem is

$31$

To solve the inequality, we proceed as follows:

1)

First, we isolate the term in x. To do that, we add -6 on both sides of the inequality, and we find:

$31-6$

So, this is now the new inequality.

2)

Then, we divide both sides of the equation by 5; we get:

$\frac{25}{5}$

3)

Finally, we change sign to the inequality, so we get:

$x$

So, the student's error is that he subtracted -5 from both sides, not -6.