Using the perimeter of a rectangle, it is found that she can make a deck of 122 ft wide.
<h3>What is the perimeter of a rectangle?</h3>
The perimeter of a rectangle of length l and width w is given by:

In this problem:
- She has enough wood to build a deck that is 280ft, hence P = 280.
- The length is of 10 feet, hence l = 10.
- Considering that the deck's width will be added to the actual width of 8 feet, we have that w = 8 + w.
Then:






She can make a deck of 122 ft wide.
You can learn more about the perimeter of a rectangle at brainly.com/question/10489198
Answer:
The solution is x=4.75 and y = -22
Step-by-step explanation:
To find the solution to the system of equations, we will follow the steps below:
3.2x + 0.5y = 4.2 --------------------------------------------------------------------------(1)
-1.6x -0.5y = 3.4 ----------------------------------------------------------------------------(2)
add equation (1) and equation (2)
1.6x =7.6
Divide both-side of the equation by 1.6 to get the value of x
1.6x /1.6 =7.6/1.6
x =4.75
substitute x = 4.75 into equation (1) and solve for y
3.2(4.75) + 0.5y = 4.2
15.2 + 0.5y = 4.2
subtract 15.2 from both-side of the equation
15.2 - 15.2 + 0.5y = 4.2-15.2
0.5y = -11
Divide both-side of the equation by 0.5
0.5y/0.5 = -11/0.5
y = -22
The solution is x=4.75 and y = -22
The volume at time <span>t = 25 seconds
since </span><span> V = 4 sqrt(t) cm3,
V(5)= 4*</span><span>sqrt(25)cm^3=4*5=20cm^3</span>