4n -12 >n
4n > n + 12
3n > 12
n > 4
So 5,6,7,8,9, and so on
X represents the length of a deck. There are three parts to this equations. The 1. width, 2. the length, and 3. the 5 feet shorter. Using the key words, y = the width of a deck (uses the term is which means =) So that takes the width part out of the equation. Then, 5 feet shorter means -5 than a number. That takes away the 5 feet shorter part of the equation. That leaves x to equal the length of the deck.
Use slip and slide method
p^2-2p-15
(p-5)(p+3)
(p-5/3)(p+3/3)
(p-5/3)(p+1)
(3p-5)(p+1)
Final answer: (3p-5)(p+1)
There are two solutions.
.. (3, 2)
.. (0.2, -3.6)
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If you're choosing possibilities from a list, trying them in the equations usually gives quick results.