Hey there!
The answer to your question is 
Given:

First, we can start by adding like terms. The following are like terms:



Now, we can add these pairs together, giving us:



Now, add all this together, and we get our answer as:

Have a terrificly amazing day!
Here is the answer for ya
Area = length x width
x² + 12x = l * x
A. First, you factor x from x² + 12x

area = x (x+12)
area = (x+12) * x
Length = x + 12
B.If
x = 10,l = x + 12 = 10 +12 = 22
length = 22
and
Area = x² + 12x = 10² + 12(10) = 100 + 120 = 220
area = 220 Hope this helps :)
For the answer to the question above,
1. If we let x as the side of the square cut-out, the formula for the capacity (volume) of the food dish is:
V = (12 - 2x)(8 - 2x)(x)
V = 96x - 40x^2 + 4x^3
To find the zeros, we equate the equation to 0, so, the values of x that would result to zero would be:
x = 0, 6, 4
2. To get the value of x to obtain the maximum capacity, we differentiate the equation, equate it to zero, and solve for x.
dV/dx = 96 - 80x + 12x^2 = 0
x = 5.10, 1.57
The value of x that would give the maximum capacity is x = 1.57
3. If the volume of the box is 12, then the value of x can be solved using:
12 = 96x - 40x^2 + 4x^3
x = 0.13, 6.22, 3.65
The permissible value of x is 0.13 and 3.65
4. Increasing the cutout of the box increases the volume until its dimension reaches 1.57. After that, the value of the volume decreases it reaches 4.
5. V = (q -2x) (p - 2x) (x)