SOLUTION: The school board is planning to expand the current schoolyard from rectangle ABCD to rectangle AEFG. If each unit of the figure above represents 1 foot, by how many feet will the p

Algebra ->  Polygons -> SOLUTION: The school board is planning to expand the current schoolyard from rectangle ABCD to rectangle AEFG. If each unit of the figure above represents 1 foot, by how many feet will the p      Log On


   

Question 676169: The school board is planning to expand the current schoolyard from rectangle ABCD to rectangle AEFG. If each unit of the figure above represents 1 foot, by how many feet will the perimeter of the schoolyard have increased after the expansion?
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Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
if one unit equal to 1ft, than:
AB=120ft
AD=80ft
so, the perimeter of ABCD is P=2AB%2B2AD
P=2%2A120ft%2B2%2A80ft
P=240ft%2B160ft
P=400ft

the perimeter P%5B1%5D of AEFG will be:
AE=180ft............here AB increased by 60 units
AG=100ft............here AD increased by 20 units
P%5B1%5D=2AE%2B2AG
P%5B1%5D=2%2A180ft%2B2%2A100ft
P%5B1%5D=360ft%2B200ft
P%5B1%5D=560ft
the schoolyard have increased after the expansion:
P%5B1%5D-P=+560ft-400ft
P%5B1%5D-P=+160ft