Answer: x=9
Step-by-step explanation:
The bottom triangle that has a 40° is an isosceles triangle, therefore the other angle at the bottom right is also 40°. This leaves the top angle to be 100°.
180=40+40+x
180=80+x
x=100
Now, to find ∠2, you can tell it is a supplementary angle. Therefore, the 2 angles add up to 180°
180-100=∠2
80°=∠2
The problem states that ∠2 is 9x-1. We know that ∠2 is 80°. We can solve for x.
80=9x-1
81=9x
x=9
 
        
             
        
        
        
The expression would me m / 7 or m and 7 as a fraction. M is on the top
        
             
        
        
        
Answer:
Step-by-step explanation:
We want to determine a 90% confidence interval for the mean amount of time that teens spend online each week.
Number of sample, n = 41
Mean, u = 43.1 hours
Standard deviation, s = 5.91 hours
For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes 
43.1 ± 1.645 × 5.91/√41
= 43.1 ± 1.645 × 0.923
= 43.1 ± 1.52
The lower end of the confidence interval is 43.1 - 1.52 =41.58
The upper end of the confidence interval is 43.1 + 1.52 =44.62
Therefore, with 90% confidence interval, the mean amount of time that teens spend online each week is between 41.58 and 44.62 
 
        
             
        
        
        
Answer:
Yes it will
Step-by-step explanation:
The equation would be 50>45+(45*.08)
Once solving it, you will get 50 >48.6