Mary Ann solves the inequality −3x≥12. Justify the steps Mary Ann takes to find the solution set.
Responses
A. Mary Ann divides both sides of the inequality by −3 and changes the inequality symbol to ≤ to get x≤−4.
B. Mary Ann divides both sides of the inequality by −3 to get x≥−4.
C. Mary Ann adds −3 to both sides of the inequality to get x≥9.
D. Mary Ann adds −3 to both sides of the inequality and changes the inequality symbol to ≤ to get x≤9.
B. Mary Ann divides both sides of the inequality by −3 to get x≥−4.
The correct answer is:
B. Mary Ann divides both sides of the inequality by -3 to get x ≥ -4.
Justification: To solve the inequality -3x ≥ 12, Mary Ann divides both sides of the inequality by -3. It is important to note that when dividing or multiplying both sides of an inequality by a negative number, the direction of the inequality sign should be flipped. Dividing both sides by -3 gives us x ≥ -4, which is the correct solution.