Answer:
Perimeter = 22 units
Area = 30 units squared
Step-by-step explanation: To find the perimeter of this figure, add the lengths of the rectangle's four sides (5+6+5+6=22). To find the area of this figure, multiply the length and width of the rectangle (5x6=30).
Answer:
k = 30, 
Step-by-step explanation:
Since
is a solution, then it must satisfy the differential equation. So, we calculate the derivatives and replace the value in the equation. We have that

Then, replacing the derivatives in the equation we have:

Since
is a positive function, we have that
.
Now, consider a general solution
, then, by calculating the derivatives and replacing them in the equation, we get

We already know that r=5 is a solution of the equation, then we can divide the polynomial by the factor (r-5) to the get the other solution. If we do so, we get that (r-6)=0. So the other solution is r=6.
Therefore, the general solution is

Answer: 6x² + 36x + 22
Step-by-step explanation:2 faces (x + 3) by (x + 7), area of both these faces 2(x+3)*(x + 7)
2 faces (x + 3) by (x - 1), area of both these faces 2(x+3)*(x - 1)
2 faces (x -1 ) by (x + 7), area of both these faces 2(x-1)*(x + 7)
Whole surface area is
2(x+3)*(x + 7) + 2(x+3)*(x - 1) + 2(x-1)*(x + 7) =
=2(x² + 3x +7x +21) + 2(x² +3x -x - 3) + 2(x² - x +7x -7)=
=2x² + 20x +42 + 2x² + 4x - 6 + 2x² + 12x -14 =
= 6x² + 36x + 22