Respuesta :
let x be the width of the sidewalk and the area becomes:
A=LW and L=6+2x and W=4+2x now we have
A=(6+2x)(4+2x) and we are told that A=48ft^2
48=24+20x+4x^2
4x^2+20x-24=0
4(x^2+5x-6)=0
x^2+5x-6=0
x^2-x+6x-6=0
x(x-1)+6(x-1)=0
(x+6)(x-1)=0
So x=-6, 1, however since x is a measurement it must be positive thus
x=width=1 ft is the only possible solution.
A=LW and L=6+2x and W=4+2x now we have
A=(6+2x)(4+2x) and we are told that A=48ft^2
48=24+20x+4x^2
4x^2+20x-24=0
4(x^2+5x-6)=0
x^2+5x-6=0
x^2-x+6x-6=0
x(x-1)+6(x-1)=0
(x+6)(x-1)=0
So x=-6, 1, however since x is a measurement it must be positive thus
x=width=1 ft is the only possible solution.
Answer:
The width of sidewalk is 1 feet.
Step-by-step explanation:
A rectangular garden is 6 feet by 4 feet.
Let sidewalk width be x feet
New length and width of garden including sidewalk width
Length = 6 + 2x
Width = 4 + 2x
Area of sidewalk and garden together is 48
Area of rectangular = L x W
(6+2x)(4+2x) = 48
[tex]4x^2+20x+24=48[/tex]
[tex]x^2+5x-6=0[/tex]
[tex](x+6)(x-1)=0[/tex]
x=-6,1
We will ignore negative 6 because width can't be negative
Hence, The width of sidewalk is 1 feet.
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