Answer:
x is less than or equal to 7
Step-by-step explanation:
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.
Answer:
x = -
, x = 
Step-by-step explanation:
The absolute value function always gives a positive value, however, the expression inside can be positive or negative, that is
- 3x + 16 = 18 or -(- 3x + 16) = 18
Solving
- 3x + 16 = 18 ( subtract 16 from both sides )
- 3x = 2 ( divide both sides by - 3 )
x = - 
or
-(- 3x + 16) = 18
3x - 16 = 18 ( add 16 to both sides )
3x = 34 ( divide both sides by 3 )
x = 
As a check
Substitute these values into the left side of the equation and if equal to the right side then they are the solutions.
| - 3(-
) + 16 | = | 2 + 16 | = | 18 | = 18 ← True
| - 3(
) + 16 | = | - 34 + 16 | = | - 18 | = 18 ← True
Thus x = -
and x =
are the solutions
Answer:1385.44mm sq
Step-by-step explanation: surface area of a circle = pi x radius squared
3.142 x 21 squared