The second T-chart which would be 
X | Y
-2. 10
-1. 5
0. 0
1. 5
2. 10
        
                    
             
        
        
        
C.
√8+3√2+√32=2√2+3√2+4√2=9√2
        
             
        
        
        
9514 1404 393
Answer:
   1000
Step-by-step explanation:
If the number of protesters per minute remains a constant, then you could write the proportion ...
   p/12 = 177/2.1
Multiplying by 12 gives ...
   p = 12(177/2.1) ≈ 1011.4
Here, minutes are given to 2 significant figures, and the initial count is given to 3 significant figures. The best you can hope for is that your estimate is good to 3 significant figures:
  1010 protesters
It is probably sufficient to report the number to 2 significant figures*:
   1000 protesters
_____
* Unfortunately, with a number like 1000, the only way you can tell it has 2 significant figures is to report it as 1.0×10³ or 10. hundreds. The trailing zeros are usually not considered significant.
 
        
             
        
        
        
Given:
Rectangle shape.
One side: 5x + 2
other side: x - 4
Area = length * width
Area = (5x+2)(x-4)
A = 5x(x-4) +2(x-4)
A = 5x² - 20x + 2x - 8
A = 5x² - 18x - 8
        
                    
             
        
        
        
Yes you are correct 20% of 150 is 30.