What lesson are you referring to
        
             
        
        
        
Answer:
What’s the problem? If you could attach the problem we can help u out!
Step-by-step explanation:
 
        
             
        
        
        
Answer:
Step-by-step explanation:
1). 
   
   Comparing exponents on both the sides.
   x² + 2x = -1
   x² + 2x + 1 = 0
   (x + 1)² = 0
   x = -1
2). 
   
   
   By comparing exponents,
   x - 3 = 3(x + 1)
   x - 3 = 3x + 3
   3x - x = 3 + 3
   2x = 6
   x = 3
3). 
    
    By comparing exponents,
    
    5 - k = 2(3 - k)
    5 - k = 6 - 2k
    2k - k = 6 - 5
     k = 1
4). 
     
     
     By comparing exponents,
     x + 3 = 3(2x + 6)
     x + 3 = 6x + 18
     6x - x = 3 - 18
     5x = - 15
      x = -3
5). 
     
     x - 2 = 0
     x = 2