The property of inequality being used in this statement is the Multiplication Property of Inequality. This property states that if a, b, and c are real numbers, and a < b and c > 0, then ac < bc. In the given statement, x < 15 and 5 is greater than 0, so we can multiply both sides of the inequality by 5. By doing this, we get 5x < 75, which satisfies the Multiplication Property of Inequality.
