You have to combine like terms, so the variable (x, y, s, d, c....) and the exponents must be the same in order to combine them.
For example:
x² + x³    Since they don't have the same exponent, you can't combine them
y² + 3y² = 4y²
23x + x = 24x
4. 2s² + 1 + s² - 2s + 1    You can rearrange it if it makes it easier
2s² + s² - 2s + 1 + 1 = 3s² - 2s + 2
5. 5t² - 2t - 1 - (3t² - 5t + 7) Distribute/multiply the - to (3t² - 5t + 7)
5t² - 2t - 1 - 3t² + 5t - 7 = 2t² + 3t - 8
Do the same for #9 and #10, and you should get:
9. 2k² + 5k - 9
10. 6y³ - 7y² - 6y - 12
 
        
             
        
        
        
The answer is approx. 10.8 per hour.
If you want to round it up, it would be 11. I prefer you not to round though as this is Money. Money should have decimals included.
        
                    
             
        
        
        
The answer is: 
(null hypothesis) u=2.7; Ha(alt hypothesis): u<2.7 
        
                    
             
        
        
        
OK SURE WHAT IS IT? SO I CAN ANSWER YOUR QUEST.?
        
             
        
        
        
Answer:
umm
Step-by-step explanation:
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