algebraic expression?

Question

The greenhouse I am building is 6 feet longer than it is wide. Write an algebraic expression for the perimeter if the length is expressed as x. If x equals 20, what is the perimeter?

Answer 1

Length = x. Length is 6' more than its width. Hence width=x-6.
Perimeter is 2*(x+x-6)=4x-12.
(Assumed to be a rectangular greenhouse)
If x=20, perimeter= 20*4-12=68.

Answer 2

Let x = width
then the length is l = x+6
Perimeter = 2(length + width) = 2(x + x + 6) = 2(2x+6) = 4(x+3)
So if x = 20 then Perimeter = 4(20+3) = 92 feet

Answer 3

Length = x
So width = x - 6

Thus perimeter = 2x + 2(x - 6)
= 4x - 12
=4(x -3) ft

If x = 20, perimeter = 4 * 17
= 68 ft

Answer 4

If it is a rectangular greenhouse:
Two sides will be length x, so their total lengthis 2*(x) = 2x
The two shorter sides will each be length x - 6, so their total length is 2*(x + 6) = 2x - 12.

The perimeter will be the sums of the lengths of the two shorter sides and the two longer ones. (2x) + (2x - 12) = 4x - 12.

If x = 20, 4x - 12= 4*20 - 12 = 80 - 12 = 68.

Wait, I see all our answers hinge one thing. Is x, which you say is 20, the length of the longer side or the shorter one? I believee you meant length to be x and width to be x - 6. Please verify.

Answer 5

let x=length. Then (x-6)=width. Perimeter=x+x+(x-6)+(x-6). Solve for perimeter if x=20.

Answer 6

an expression that could be used is
2x + 2x - 12 or 4x - 12
If x = 20, then that would be
4(20) - 12
=80 - 12
=68
the perimeter would be 68 metres

Answer 7

1.p=2[x+(x-6)]'

2,if P=20
20=2(2x-6)
2x=16
x=8
length=8 and breadth 2
edit typo
if x=20
P=2(40-6)
2*34=68'