Andy's rectangular garden is 3 times as long as it is wide.The perimeter of the garden..

...is 56m.? What are the dimensions of Andy's garden?

Perimeter = 2( Length) + 2 ( Width )
Perimter = 56 m
56 = 2( Length) + 2 ( Width )
Length = 3x
Width = x
56 = 2( 3x ) + 2 ( x )
56 = 6x + 2x
56 = 8x
7 = x

Length = 3x
Width = x
Length = 3(7)
Width = 7
Length = 21
Width = 7

Checking
Perimeter = 2( Length) + 2 ( Width )
Perimeter = 2( 21 ) + 2 ( 7 )
Perimeter = 42 + 14
Perimeter = 56m Yes

7m wide, 21m long

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