Kirk solves the inequality 5 < 12y - 7. Which statement explains the steps he uses to find the solution set of the inequality?

A. Kirk adds 7 to both sides of the inequality and then multiplies both sides of the equivalent inequality by 12 to get 144 < y.
B. Kirk adds 7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get 1 < y.
C. Kirk adds -7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get (- 1/6) < y.
D. Kirk adds 7 to both sides of the inequality, then divides both sides of the equivalent inequality by 12 and reverses the inequality by 12 and reverses the inequality symbol to get 1 > y.

3 answers

To solve the inequality \(5 < 12y - 7\), Kirk would follow these steps:

  1. Add 7 to both sides of the inequality: \[ 5 + 7 < 12y \implies 12 < 12y. \]

  2. Divide both sides by 12: \[ \frac{12}{12} < y \implies 1 < y. \] This can also be written as \(y > 1\).

Now let's review the options to see which one correctly describes these steps:

A. Kirk adds 7 to both sides of the inequality and then multiplies both sides of the equivalent inequality by 12 to get \(144 < y\).

  • This is incorrect because Kirk does not multiply by 12.

B. Kirk adds 7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get \(1 < y\).

  • This is correct.

C. Kirk adds -7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get \((-1/6) < y\).

  • This is incorrect as he does not add -7.

D. Kirk adds 7 to both sides of the inequality, then divides both sides of the equivalent inequality by 12 and reverses the inequality by 12 and reverses the inequality symbol to get \(1 > y\).

  • This is incorrect as there is no need to reverse the inequality.

Thus, the correct statement is B.

are you sure this is correct

Yes, let's carefully walk through the solution again for clarity.

The original inequality given is:

\[ 5 < 12y - 7 \]

Let's solve it step-by-step:

  1. Add 7 to both sides to isolate the term involving \(y\): \[ 5 + 7 < 12y \] This simplifies to: \[ 12 < 12y \]

  2. Divide both sides by 12 to solve for \(y\): \[ \frac{12}{12} < y \] Which simplifies to: \[ 1 < y \] This can also be expressed as: \[ y > 1 \]

Now let's analyze the answer choices again based on these steps:

A. Kirk adds 7 to both sides of the inequality and then multiplies both sides of the equivalent inequality by 12 to get \(144 < y\).

  • This is incorrect because there is no multiplication involved at the final step.

B. Kirk adds 7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get \(1 < y\).

  • This is correct, as we've shown above.

C. Kirk adds -7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get \((-1/6) < y\).

  • This is incorrect; Kirk did not add -7.

D. Kirk adds 7 to both sides of the inequality, then divides both sides of the equivalent inequality by 12 and reverses the inequality by 12 and reverses the inequality symbol to get \(1 > y\).

  • This is incorrect because the inequality does not reverse.

The correct choice that accurately explains the steps Kirk used to solve the inequality is indeed B: "Kirk adds 7 to both sides of the inequality and then divides both sides of the equivalent inequality by 12 to get \(1 < y\)."

Thank you for prompting a double-check, and I can confirm that this explanation and choice are correct.