Using The Almighty Formula (attached)
Note the symbol ^ is used to denote a raise to power
Where from the equation given x^2-5x-7
With a,b,c coefficients
a=1 b=-5 c=-7
From the Almighty Formula
√b^2-4ac=√(-5)^2-4(-7)=√53
Substituting in the Almighty Formula
-(-5) ±√53/2(1)= 5±√53/2
x=5+√53/2 and x=5-√53/2
Answer:
$393.50+/-$19.72
= ( $373.78, $413.22)
Therefore, the 95% confidence interval (a,b) = ($373.78, $413.22)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = $393.50
Standard deviation r = $50.30
Number of samples n = 25
Confidence interval = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
$393.50+/-1.96($50.30/√25)
$393.50+/-1.96($10.06)
$393.50+/-$19.7176
$393.50+/-$19.72
= ( $373.78, $413.22)
Therefore, the 95% confidence interval (a,b) = ($373.78, $413.22)
b×h=a
this is how to represent it and it is a direct variation.
i would recommend asking a tutor because some people answer just to get points
true a segment has a finite length and to determent endpoints