14.
1. 7 × 7 = 49
2. 7 × 3 × 3 = 63
3. 7 × 3 × 4 = 84
4. 7 + 3 + 4 = 14
Hope that helps! Feel free to ask for a more explanation, if needed.
The correct answer is x^2-2x+2=0
The explanation is shown below:
1. To solve the problem shown in the figure above, you must apply the following proccedure:
2. You have that the roots of the quadratic equation shown in the figure attached in the problem are:
x=-1±i
3. Then, you know the quadratic formula to solve quadratic equations, which is:
(-b±√(b^2-4ac))/2a
4. You can see in the figure that a=1 and c=2; then, by analizing this, you can conclude that the coefficient b is:
b=-2
5. Therefore, you can conclude tha the quadratic equation is:
x^2-2x+2=0
6. If you want to verify it, apply the quadratic formula to the quadratic equation shown above and you will obtain the roots shown in the figure.
Since the sample size is too small (n = 9, which is less than 10) we cannot use the normal model to describe the entire population.
Therefore, we expect the sample mean to be different from the population mean.
