I believe this is correct
Answer:
And we are 95% confident that the true difference means are between 
Step-by-step explanation:
We know the following info:
sample mean for group 1
sample mean for group 2
sample standard deviation for group 1
sample standard deviation for group 2
sample size group 1
sample size group 2
We want to find a confidence interval for the difference of means and the correct formula to do this is:
Now we just need to find the critical value. The confidence level is 0.95 then the significance is 
and 
. The degrees of freedom are given by:
The critical value for this case would be :
And replacing into the confidence interval formula we got:
And we are 95% confident that the true difference means are between
Answer:
a) Upwards
b) x = -1
c) (-1,-9)
d) x intercepts; (2,0) and (-4,0)
y intercept is (0,-8)
Step-by-step explanation:
a) As we can see, the parabola faces upwards
b) To find the axis of symmetry equation, we look at the plot of the graph and see the point through the vertex of the parabola that exactly divides the parabola into two equal parts
The x-value that the line passes through here is the point x = -1 and that is the equation of the axis of symmetry
c) The vertex represents the lowest point of the circle here,
As we can see, this is the point through which the axis of symmetry passes through to make a symmetrical division of the parabola
We have the coordinates of this point as
(-1,-9)
d) The intercepts
The x-intercept are the two points in which the parabola crosses the x-axis
We have this point as 2 and -4
The x-intercepts are at the points (2,0) and (-4,0)
For the y-intercept; it is the y-coordinate of the point at which the parabola crosses the y-axis and this is the point (0,-8)
75 ÷ 15 = 5
Riley can cut 5 strips of ribbon each 15 inches long
I believe this is D. The transitive property
