Answer:
It is a solution
Step-by-step explanation:
y = -4x - 8
Let x = -9 and y = 28
Substitute these values in
28 = -4(-9) -8
28 = 36 -8
28 =28
This is true so it is a solution
Answer:
Company B.
Step-by-step explanation:
On the graph, when x is 1, y is 50. That means it is $50 for one window. On the chart, when there is 1 window, the cost is $55. So, company B is more expensive!
Answer:
the middle 50% of most lengths of pregnancies ranges between 255.62 days and 274.38 days
Step-by-step explanation:
Given that :
Mean = 265
standard deviation = 14
The formula for calculating the z score is 
x = μ + σz
At middle of 50% i.e 0.50
The critical value for 
From standard normal table
+ 0.67 or -0.67
So; when z = -0.67
x = μ + σz
x = 265 + 14(-0.67)
x = 265 -9.38
x = 255.62
when z = +0.67
x = μ + σz
x = 265 + 14 (0.67)
x = 265 + 9.38
x = 274.38
the middle 50% of most lengths of pregnancies ranges between 255.62 days and 274.38 days