Sophie, Adola, and Gilly are debating potential values in the solution set of the compound inequality −2≤2x−2<8 . Sophie says that −2 is a solution. Adola says that 5 is a solution. Gilly says that 2 is a solution. Which person is correct? Enter 1 for Sophie, 2 for Adola, or 3 for Gilly.(1 point)

The person who is correct is person .

1 answer

To find out who is correct, we need to solve the compound inequality \( -2 \leq 2x - 2 < 8 \).

  1. Break the compound inequality into two parts:

    \(-2 \leq 2x - 2\)

    and

    \(2x - 2 < 8\).

  2. Solve the first part:

    \(-2 \leq 2x - 2\)

    Add 2 to both sides:

    \(-2 + 2 \leq 2x\)

    \(0 \leq 2x\)

    Divide both sides by 2:

    \(0 \leq x\) or \(x \geq 0\).

  3. Solve the second part:

    \(2x - 2 < 8\)

    Add 2 to both sides:

    \(2x < 8 + 2\)

    \(2x < 10\)

    Divide both sides by 2:

    \(x < 5\).

  4. Combine the results:

    The solution to the compound inequality is:

    \(0 \leq x < 5\)

    This means \(x\) can be any value starting from \(0\) up to but not including \(5\).

  5. Evaluate each person's claim:

    • Sophie claims \( -2 \) is a solution:

      • \( -2 \) is not within the interval \( [0, 5) \).
    • Adola claims \( 5 \) is a solution:

      • \( 5 \) is also not within the interval \( [0, 5) \) (it is at the boundary and not included).
    • Gilly claims \( 2 \) is a solution:

      • \( 2 \) is within the interval \( [0, 5) \).

So, Gilly is the only one who is correct.

The person who is correct is person 3.