Question

Rachel multiplied each side of ≥x greater than or equal to 2 by 3. She wrote the result as ≤3 x less than or equal to 6 . Explain the error Rachel made.

Answer 1

Rachel's error is in the inequality sign

Explanation:

Given

`x \geq 2`

Required

Determine the error in Rachel's workings

From the question, we understand that both sides of the inequality were multiplied by 3

i.e.

`3 * x \geq 2 * 3`

This gives

`3 x \geq 6`

Comparing this to Rachel's result:
`3 x \leq 6`

We can conclude that Rachel's error is in the inequality sign.

The sign of an inequality will only change is it is being multiplied or divided by a negative number; otherwise, the sign remains unchanged