Answer:
4
Step-by-step explanation:
All the sides of an equilateral triangle are equal, hence the perimeter is expressed as P = 3s
s is one of the side length
Given  DE = 5x - 8
P = 3DE
P = 3(5x-8)
36 = 3(5x-8)
36/3 = 5x-8
12 = 5x - 8
5x = 12+9
5x = 20
x = 20/4
x = 4
Hence the value of x is 4
 
        
             
        
        
        
I think it's B.............
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
9.  Correct, D
-3Y + 9X <= 12
3Y - 9X => -12
3Y => -12 + 9X  
Y => -4 + 3X  
10.  D
11.  D
12.  Correct, B
13.  Correct, E
14.  A
15.  B
 
        
             
        
        
        
Answer:
54 degrees
Step-by-step explanation:
No matter the categorization of a triangle the total degrees present will equal 180. You know that you have a corner that equals 44 degrees and another that is 82 degrees. Add the 44 + 82 degrees to get 126 degrees. After getting the 126 degrees, minus that from the total of 180 to get 54 degrees. 
 
        
             
        
        
        
Answer:
7
Step-by-step explanation:
When working with order of operations, use the acronym 'PEMDAS' (Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.) 
The equation should basically be done in that order.
There are no parenthesis,
no exponents,
But there IS multiplication.
1 x 10 = 10.
So now, what is left over is 10 - 3.
There addition, but there IS subtraction.
10 - 3 = 7.
7 is what is left over.
Therefore, 1 x 10 - 3 in standard form is 7.