Answer :
The value of x of the first rectangular deck is 8.
For given question,
The perimeter of a one rectangular deck is 78 feet.
The length of the first rectangular deck is represented as (2x + 3), and its width is represented as (3x-4).
Similarly, the perimeter of a second rectangular deck is 2 times the perimeter of the first deck with a length of (4x + 6) and a width of (6x -1).
We need to find the value of x of the first rectangular deck.
Let P1 be the perimeter of the first rectangular deck.
⇒ P1 = 2 × (length + width)
⇒ 78 = 2 × [(2x + 3) + (3x - 4)]
⇒ 39 = (2x + 3x + 3 - 4)
⇒ 39 = 5x - 1
⇒ 40 = 5x
⇒ x = 40/5
⇒ x = 8
Therefore, the value of x of the first rectangular deck is 8.
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