The coefficients are the numbers next to a variable (which is X in this case). Therefore, the coefficients here are 4 and 8
        
             
        
        
        
Answer:
The expression to show the average daily change in temperature can be given by :
⇒  °C
°C
Step-by-step explanation:
Changes in the temperature of city as reported by newspaper :
Day 1: 2.64° C
Day 2:  °C
°C
Day 3: -0.35°C
Day 4:  °C
°C
The average daily change in temperature can be calculated as 
⇒  °C
°C
The fractions can be written in decimals
⇒  °C
°C
⇒  °C
°C
⇒  °C [Average daily change in temperature.]
°C [Average daily change in temperature.]
 
        
             
        
        
        
Answer:
(21 + 11)2 = 64
So, I don't think teachers do this, but this is my way of doing it
Okay, so first, I divided 64 by 2 : 
64 ÷ 2 = 32
Then, I subtracted 11 from 32:
21 
Now, to check, just do the problem :
(21 + 11)2 = 64
       32 * 2 = 64