Answer: 
Step-by-step explanation:
 Given the equation  you need to solve for the variable "b".
 you need to solve for the variable "b".
 You need to apply Distributive property on both sides of the equation:
 
 Now you need to add 21 to both sides of the equation:
 
 Subtract  from both sides:
 from both sides:
 
 And finally, you can divide both sides of the equation by 18:
 
 
        
                    
             
        
        
        
Isnt it 2.5 and ur welcome
        
             
        
        
        
<span>
<u><em>First, we need to get the amount of change:</em></u>The amount of change can either be an increase or a decrease.
It can be calculated as follows:
amount of change = </span>

<span>
If the amount of change is positive, then it is an increase
If the amount of change is negative, then it is a decrease
<u><em>Then, we need to convert this amount into a percentage:</em></u>Changing the amount into a percentage can simply be done by multiplying this amount by 100
This means that:
% of change = amount of change * 100
<u><em>Combining the two steps:</em></u>% of change = </span>

<span> * 100
<u>Examples:</u>The original price of a certain product was $10. It then became $12. Find the % of increase.
% of change = </span>

<span> = 20%
This means that the price increased by 20%
The temperature decreased from 25 degrees to 20 degrees. Find the percentage of decrease.
% of decrease = </span>

<span> = -20%
This means that the temperature decreased by 20%
Hope this helps :)</span>
 
        
        
        
Divide both sides by -2
two negatives make a positive and that's true so x = 16/2 so divide it
x = 8 because 2 x 8 = 16 and 2/16 = 8 so true.
Answer: x = 8.