Peter is going to put up 5 walls in the tree house. each wall will be 7 feet high and 7 feet across. he wants to leave room for windows that measure 2 feet by 2 feet. which algebraic expressions will give the total square feet of lumber he will need for the walls if n represents the number of windows he puts in? choose all that apply.

To find the amount of lumber Peter will need, you will subtract the amount of space needed for the windows from the total area of the 5 walls.

Area of all 5 walls - area of the windows.

5 groups of 49 square feet - n groups of 4 square feet.

5(7 x 7) - n(2 x 2)

245 - 4n would be the simplified expression representing the amount of lumber needed.