Answer:
A. (1, -2)
B. the lines intersect at the solution point: (1, -2).
Step-by-step explanation:
A. The equations can be solve by substitution by using the y-expression provided by one of them to substitute for y in the other.
This gives ...
3x -5 = 6x -8
Adding 8-3x to both sides, we get ...
3 = 3x
Dividing both sides by 3 gives ...
1 = x
Substituting this value into the first equation, we can find y:
y = 3(1) -5 = -2
The solution is (x, y) = (1, -2).
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B. The lines intersect at the solution point, the point that satisfies both equations simultaneously. That point is (1, -2).
Answer: 11.5%
Explanation:Since 1 minute = 60 seconds, we multiply 12 minutes by 60 so that 12 minutes = 720 seconds. Thus, we're looking for a probability that the auditor will spend more than 720 seconds.
Now, we get the z-score for 720 seconds by the following formula:

where

So, the z-score of 720 seconds is given by:

Let
t = time for the auditor to finish his work
z = z-score of time t
Since the time is normally distributed, the probability for t > 720 is the same as the probability for z > 1.2. In terms of equation:

Hence, there is
11.5% chance that the auditor will spend more than 12 minutes in an invoice.
The answer would be letter B.