Answer:
The probability that either Alex or Bryan get an A is 0.9
Step-by-step explanation:
Before we proceed to answer, we shall be making some important notation;
Let A = event of Alex getting an A
Let B = event of Bryan getting an A
From the question, P(A) = 0.9, P(B) = 0.8 and P(A ∩  ) = 0.1
 ) = 0.1
We are to calculate the probability that either Alex or Bryan get an A which can be represented as P(A ∪ B)
We can use the addition theorem here;
P(A ∪ B) = P(A) + P(B) - P(A ∩ B)  .......................(i)
Also,
P(A) = P(A ∩  )  +   P(A ∩ B)   .........................(ii)
 )  +   P(A ∩ B)   .........................(ii)
We can insert ii into i and we have;
P(A ∪ B) =  P(A ∩  )  +   P(A ∩ B)  + P(B) - P(A ∩ B) =   P(A ∩
 )  +   P(A ∩ B)  + P(B) - P(A ∩ B) =   P(A ∩  ) + P(B) = 0.1 + 0.8 = 0.9
 ) + P(B) = 0.1 + 0.8 = 0.9
 
        
             
        
        
        
Answer:
2
Step-by-step explantion: 
This isnt following by the formula but if you look at the pattern ir adds 2 every time
 
        
             
        
        
        
They are similar because they both contain  variables.
        
             
        
        
        
To determine the length of AB, one must subtract BC from AC. If the length of AC is 18 and the length of BC is 4, then using this formula yields 18 - 4 = 14, so the length of AB is 14.
This postulate also allows a line segment that has only two known points to be broken into two line segments with the addition of a third point in between the endpoints. This is useful for proofs in geometry and analysis.
 
        
                    
             
        
        
        
We can start by getting rid of parenthesis:
4x-3x+6=21
Then we can combine like terms:
x=21-6
x=15
So our end product is x=15.
Hope I helped soz if I'm wrong ouo.
~Potato.
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