Answer:
2010.
Step-by-step explanation:
We have been given an exponential growth formula  , which represents number of passengers traveling by airplane since 1990.
, which represents number of passengers traveling by airplane since 1990.
To find the year in which 900 million passengers will travel by airline, we will equate the given formula by 900 and solve for t as:



Take natural log of both sides:

Using property  , we will get:
, we will get:




This means that in the 20th year since 1990, 900 million passengers would travel by airline.

Therefore, 900 million passengers would travel by airline in 2010.
 
        
             
        
        
        
Answer:
Since both terms are perfect squares, factor using the difference of squares formula.
(x+9y)(x−9y)
 
        
                    
             
        
        
        
Answer:
186
Step-by-step explanation:
 
        
             
        
        
        
The square root of -48 is 2 because 2x2x2x2x2x2x is not -48
        
             
        
        
        
It is given that line segment BC is congruent to line segment EC and that line segment AC is congruent to DC. Because of the vertical angles theorem, angle BCA is equal to angle DCE. Therefore, triangles CBA AND DEC are congruent by SAS. Using CPCTC, BA is equal to ED.