Answer:
This system has one solution (x=2 and y=2), then the answer is A.
Step-by-step explanation:
The system of equations is:
(1)
(2)
Let's multiply the first equation by 2 and subtract it to the second equation


Using this value in (1) we can find y.


Therefore, this system has one solution (x=2 and y=2), the answer is A.
I hope it helps you!
Z value is a numerical measurement that describe a value relationship to the mean of a group of values. The standard deviations is 1.25 above the mean is 14,500 hours.
<h3>
Given information-</h3>
The mean for the bulb is 12,000 hours.
The standard deviation for the bulb is 2000 hours.
Sample value is 14500.
To find out the how many standard deviation is 14500 mean away from the mean the z value of the mean should be calculated.
<h3>Z value</h3>
Z value is a numerical measurement that describe a value relationship to the mean of a group of values. Z value is the ratio of the difference of the sample value
and mean
to the standard deviation. Thus the z value for the given mean
is,



Thus the standard deviations is 1.25 above the mean is 14,500 hours.
Learn more about the z value here;
brainly.com/question/62233
Answer:
I recoment using the formula because its different ways its taught
Step-by-step explanation:
maybe look up different formula's
The rational numbers would be 3.99 and 4 while there are no irrational number. A rational number is a number that can be written as a fraction for 3.99 it can be written as 399/100 and its the simplest form of the fraction. Also, 4 is a rational number since it can be written as 4/1 which is a fraction.