Answer:
4 ft.
Step-by-step explanation:
We can consider the orignial square's sides to be x, so area of the original figure: 
The new rectangle's sides will be x and x+8, so the area of the new figure will be x^2+8x.
We know that the new area is 3 times the old one. So our equation will be:
x^2+8x=3x^2
our answer will be x=4.
Therfore, the length of the side of the old flower bed is 4 ft.
Answer:
1)
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2)
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3)
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4)
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Step-by-step explanation:
<u>Verify each case</u>
case 1) 
<em>Find the area with the original dimensions</em>

Reduce the area of the poster by one-third

therefore
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case 2) 
<em>Find the area with the original dimensions</em>

Reduce the area of the poster by one-third

therefore
--------> 
case 3) 
<em>Find the area with the original dimensions</em>

Reduce the area of the poster by one-third

therefore
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case 4) 
<em>Find the area with the original dimensions</em>

Reduce the area of the poster by one-third

therefore
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It skips by 6 if that's what you mean
2/3 × 6 is 6/3, which would simplify to 2. 4/5 × 7 is 28/5, which would simplify to 5 3/5. so 4/5×7 is larger