Simplify both sides if needed. The left-hand side needs simplification.
4(x - 6)

-2x + 6
4x - 24

-2x + 6
All is left to do is add and subtract to get the x variable all alone.
4x - 24

-2x + 6
6x - 24

6 <-- Add 2x to both sides
6x

30 <-- Add 24 to both sides
x

5 <-- Divide both sides by 6
In order to be in the solution set, x has to be less than or equal to 5.
In interval notation: [5, -∞)
<span>Let the extension of the length and width be x.
The new dimensions are: Length = 8+x
Width =3+x
Area = 104 ft squared
Area of a rectangle = Length x Width
Therefore,
(8+x)(3+x) = 104
x^2 +11x +24=104
x^2 +11x +24-104=0
x^2 +11x-80=0
Factorize using splitting the middle term method.
X^2 +16x-5x-80=0
x(x+16)-5(x+16)=0
(x-5)(x+16)=0
either x-5 = 0 or x+16=0
x=5 or x=-16
length and width measure cannot be negative.
Therefore, the extension of the length and width is 5 feet each.</span>