Aschool is selling 5 mechanical pencils for 4.27. what factor could be used to calculate the cost of 54 pencils

Well, quite literally, 54/5 could be usedYou can't really simplify that.

Given dimensions of a rectangular garden are:

length = 2(x+6) feet

width = 3.5x feet

using the distributive property on length we get, length = 2x+12

Perimeter of a rectangle is 2(length+width)

So, P = 2(2x+12+3.5x)

Solving it we get,

P = 2(5.5x +12)   ..............adding like terms

P = .............multiplying and adding

P = 11x+24

So, perimeter is 11x+24 feet. This value of fencing will be needed.