Peter wants to use 75-watt lightbulbs and other electronics in his tree house. He has one outlet with a maximum of 900 watts. Which expression represents how much wattage remains if n is the number of lightbulbs turned on?

Expression is 900 - 75n

Step-by-step explanation:

Step 1: Maximum watts that can be used is 900W. Find amount of watts used by n light bulbs.

⇒ Watts used by n light bulbs = 75 * n = 75n

Step 2: To find the remaining amount of wattage, subtract the maximum possible W and the watts used by the light bulbs.

⇒ 900 - 75n

900-75n