Answer:
Relevant domain: [0 40]
Relevant range: [0 80]
Step-by-step explanation:
We have the following function:

In which C(t) is the water temperature.
t is the time.
The colling period ends when the water freezes (0°).
So it freezes after t minutes, and t is found when C(t) = 0. So





Relevant domain:
Input value of the function, which is in minutes. So between 0(initial) and 40(when the water freezes).
Relevant range:
Initial temperature, which is C(0) = 80, until it freezes, 0. So from 0 to 80.
Answer:
12
Step-by-step explanation:
The area of a parallelogram is equal to its base times its height. Segment DX is a height relative to the base BC, so (area of ABCD) = BC times DX,
144 = 12 times DX.
So, DX is 12. :)
Answer:
(x, y) = (5, 1)
Step-by-step explanation:
To <em>eliminate</em> x, you can double the second equation and subtract the first.
... 2(x +4y) -(2x -3y) = 2(9) -(7)
...11y = 11 . . . . . simplify
... y = 1 . . . . . . divide by 11
Using the second equation to find x, we have ...
... x + 4·1 = 9
... x = 5 . . . . . subtract 4
_____
<u>Check</u>
2·5 -3·1 = 10 -3 = 7 . . . . agrees with the first equation
(Since we used the second equation to find x, we know it will check.)
The answer for this problem is39906