When there's no number in front of a variable, that means it has a coefficient of 1.
So the coefficient is 1. Hope that makes sense.
 
        
                    
             
        
        
        
X + 6 + x + 8 + x = 53
3x + 14 = 53
3x = 39
x = 13 and the other 2 pieces are
19 and 
21
        
             
        
        
        
x = 4, y = 1
Step 1: use the equations given to find an equation with only 1 term. Here I used x. 
(x + 2y) + (x - 2y) = 2x = 6 + 2 = 8
2x = 8
x = 4
Step 2: substitute x = 4 into either given equation. Here I used the first equation x + 2y = 6.
(4 + 2y) = 6
2y = 6 - 4 = 2
y = 1
This solution can also be done by finding y in step 1 or using the other given equation in step 2. 
Hope this helped!
 
        
             
        
        
        
Answer:
C
Step-by-step explanation:
There’s nothing hard with this
You need to know special right triangles
This is a 30,60, 90 triangle
We automatically know becuase theres. Right angle (90) and a 60 degree angle
now the formula is the smallest side is (n) {I’m using N becuase theres already an X) or in this case, 6
The hypotenuse, the one directly above the 2nd biggest side, or the diagnoal side is 2n or (12). Now we know what X is in this situation which is 12. So that narrows it to 2 answers 
Now the side on the bottom of the hypotenuse, the second biggest side is used in the formula N . So we know what N is in the beginning, 6 so we just plug that in and well get C. Attached is a photo on q 30, 60, 90 special right triangle
. So we know what N is in the beginning, 6 so we just plug that in and well get C. Attached is a photo on q 30, 60, 90 special right triangle