Answer:
B and I 
Step-by-step explanation:
1 x 3 = 3
2 x 3 = 6
3 x 3 = 9
etc.
12 x 3 = 36
 
        
             
        
        
        
I believe you are expected to simplify. To do this all you do is group like terms (x, x², x³ etc.) and then simplify the coefficients. 
13. 10z + 7z - 19z² - 5z² - 17z 
first you can rearrange and group like terms (remember the bring the sign in front of each term with it). I would do it like this: 
-19z² - 5z² +10z + 7z - 17z
Now simplify the coefficients: 
-24z² + 0z 
you can omit the 0z and your simplified answer is 
-24z²
Main thing to remember here is that z and z² cannot be simplified together, nor can any variable that has an exponent because the exponent makes them differ. 
        
             
        
        
        
A. 4x+10
B. 9x+3
These are the answers to the questions. You just add the like terms together and BAM! You're answer. Hope this helps (:
        
             
        
        
        
25% is equal to 1/4 so that means 90 is 1 out of 4 peaces of that number so you are ganna want to multiplay 90 X 4 to get your answer