Answer:
a) see below
b) 40x20 meters
Step-by-step explanation:
Write down what you know:
- The area of the enclosure is length*width, so
- The length of the fencing is 80 meters, so
Now we have to combine these two equations above, and get rid of y in the process.
First rewrite the second as:
Then substitute for y in the first:
b) To maximize A, find the zero of the first derivative:
So y = (80-40)/2 = 20 meters.
Bob need to paint 205 square feet.
Solution:
Length of the door = 7 ft
Breadth of the door = 5 ft
Area of the door = length × breadth
= 7 × 5
= 35
Area of the door = 35 ft²
The given image is a trapezoid.
Top base = 12 ft
Bottom base = 20 ft
Area of the trapezoid =
= 240
Area of the trapezoid = 240 ft²
Surface area to paint = Area of the trapezoid – Area of the door
= 240 ft² – 35 ft²
= 205 ft²
Hence Bob need to paint 205 square feet.
Answer:
<em>The value of y when x has a value of 9 is 18</em>
Step-by-step explanation:
<u>Functions</u>
The variables x and y are said to have a quadratic relationship. That information is not enough to set up a general equation for both variables.
Furthermore, we know that tripling the value of x causes the value of y to be multiplied by 9. That leads us to establish a proportional equation between them, as follows:
Where k is an unknown constant.
Let's use the given point (3,2) to find the value of k:
Solving for k:
The equation is now:
Now find y when x=9:
The value of y when x has a value of 9 is 18