What is the nature of the roots for y=x2 - 4x + 4?

x = 2

Step-by-step explanation by completing the square:

Solve for x:

x^2 - 4 x + 4 = 0

Write the left hand side as a square:

(x - 2)^2 = 0

Take the square root of both sides:

x - 2 = 0

Add 2 to both sides:

 x = 2

"A z-score is the number of standard deviations between a specific observation and the mean. Here, the specific observation is 91 for each company.For Company C, the difference between their mean and 91 is 93.5 - 91 = 2.5. Since the standard deviation for Company C is 2.4, the z score is 2.5 / 2.4 = 1.04.For Company D, difference between their mean and 91 is 95.9 - 91 = 4.9. Since the standard deviation for Company D is 2.9, the z score is 4.9 / 2.9 = 1.69."