Answer:
cos(a + b) = 
Step-by-step explanation:
cos(a + b) = cos(a).cos(b) - sin(a).sin(b) [Identity]
cos(a) = 
cos(b) = 
Since, terminal side of angle 'a' lies in quadrant 3, sine of angle 'a' will be negative.
sin(a) =  [Since, sin(a) =
 [Since, sin(a) =  ]
]
          = 
          = 
Similarly, terminal side of angle 'b' lies in quadrant 2, sine of angle 'b' will be  negative.
sin(b) =  
 
          = 
          = 
By substituting these values in the identity,
cos(a + b) = 
                 = 
                 = 
                 = 
Therefore, cos(a + b) = 
 
        
             
        
        
        
 10.5 and 8.4 ......................,,,,,
        
                    
             
        
        
        
The number is 14
Here's the solution:
Let the number be x
According to the question,
27+7x=125
//Subtract 27 from both the sides
7x=125-27
7x=98
//divide both the sides by 7
x=98/7
x=14
        
                    
             
        
        
        
Answer:
C
Step-by-step explanation:
I'm super sorry if I get this wrong you don't have to choose C I feel like I'm wrong but have a nice day
 
        
             
        
        
        
I'm assuming this is a Pythagorean theorem problem. If so the answer would be √125