Answer
$[-9,6]$, see figure.
Work Step by Step
Step 1. Given $|2x+3|\leq15$, we can rewrite the inequality as $-15\leq (2x+3)\leq 15$
Step 2. Solve the above inequality as $-18\leq 2x\leq 12$ which gives $-9\leq x\leq 6$
Step 3. The above result can be represented in the interval form as $[-9,6]$
Step 4. Show the above interval on a number line as in the figure.
