Answer:
6
Step-by-step explanation:
Step 1: equal any two of the three equations together
2x + 3 = 3x - 9
Step 2: isolate the variable
3 = x - 9
6 = x
It is quadratic since a quadratic function is of the form :y=ax²+bx+c ,a,b,c are constants.
Answer:
I chose B. 3
Step-by-step explanation:
I chose B because the person is either staying still, not moving, or something of the sort.
For this case we must solve the following system of equations:

We clear x of both equations:

We match:

We find the value of "x":

Thus, the solution of the system is:

Answer:

Using the normal distribution, it is found that the replacement time that separates the top 18% from the bottom 82% is of 11.23 years.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean
and standard deviation
is given by:

- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
In this problem, the mean and the standard deviation are, respectively, given by
.
The desired value is the 82nd percentile, which is X when Z = 0.915, hence:


X - 9.4 = 0.915(2)
X = 11.23
The replacement time that separates the top 18% from the bottom 82% is of 11.23 years.
More can be learned about the normal distribution at brainly.com/question/24663213