Select the correct representation of the inequality in interval notation. $x \leq 9$
A) $[ 9 , \infty )$
B) $[ - \infty , 9 ]$
C) $\quad ( 9 , \infty )$
D) $\quad ( - \infty , 9 ]$
E) $\quad ( - \infty , 9 )$

Question

Quizplus · Accepted Answer

In interval notation, "[]" denotes a closed interval (including the number) and "()" denotes an open interval (excluding the number). Since the inequality includes the value 9, we need to use a closed bracket on 9. Additionally, since the inequality includes values less than 9, we need to use an open bracket on negative infinity, so the correct interval is (-∞, 9]. Thus, the answer is D.

Select the Correct Representation of the Inequality in Interval Notation x≤9x \leq 9x≤9

Select the Correct Representation of the Inequality in Interval Notation $x \leq 9$