Answer:
We reject the null hypothesis and accept the alternate hypothesis. Thus, it be concluded that the population mean is less than 20.          
Step-by-step explanation:
We are given the following in the question:
Population mean, μ = 60
Sample mean,  = 19.5
 = 19.5
Sample size, n = 60
Alpha, α = 0.05
Population standard deviation, σ = 1.8
First, we design the null and the alternate hypothesis
 
We use One-tailed z test to perform this hypothesis.
Formula:
 
Putting all the values, we have
 
Now,  
Since,  
 
We reject the null hypothesis and accept the alternate hypothesis. Thus, it be concluded that the population mean is less than 20.
 
        
             
        
        
        
Answer:
(x-5)(x+4)
Step-by-step explanation:
hope it helps
 
        
             
        
        
        
This is an answer of this question
 
        
        
        
Answer:
x = -3/5
Step-by-step explanation:
y = 10x + 6
0 (- 6) = 10x + 6 (- 6)
-6/10 = 10x/10
-6/10 = x
-3/5 = x