You can put this solution on YOUR website! They're on a number line. The [ and ] represent "greater than or equal to" (or less than or equal to); ( and ) represent "strictly greater than" (or strictly less than). The interval [-4, 10] denotes a set of all real numbers between -4 and 10, inclusive. (-4, 10] denotes the set of all numbers strictly greater than -4 and less than or equal to 10.