Answer:
See below.
Step-by-step explanation:
This is focusing on the order of operations.
PEMDAS = Parenthesis, exponents, multiplication, division, addition, subtraction.
40 ÷ [(18 - 9) - (13 - 12)]
40 ÷ [9 - 1]
40 ÷ 8
5
[(13 - 9) · 3] + [(14 - 8) · 2]
[4 · 3] + [6 · 2]
12 + 12
24
 
        
             
        
        
        
The answer for the question shown above is the first option, which is: 
 - Direct.
 The explanation is shown below:
 1. The problem says that <span>The number of tons of coal  varies as the number of hours.
 2. Therefore, you can write the following equation:
 number of tons:x
 number of hours:y
 x=ky
 Where k is the constant of variation.
 3. Therere the variation is direct.</span>
        
                    
             
        
        
        
8c -c= 7c
7c+6=48
7c=42
c=6
CHECK:
8(6)-(6)+6=48
48-6=42
42+6=48
48=48
        
             
        
        
        
Answer:
b
Step-by-step explanation:
because 
 
        
             
        
        
        
Given:
In triangle ABC, point D is the centroid, and BD = 6.
To find:
The measure of side BE.
Solution:
We know that the centroid divides each median in 2:1.
In the given figure BE is a median and point D is the centroid. It means point D divides the segment BE in 2:1.
Let BD and DE are 2x and x respectively.
We have, BD = 6 units.



Now,




Therefore, the measure of side BE is 9 units.