Original bus impedance matrix   
 
    0.4774405i    0.3705997i    0.4019598i    0.4142155i  
    0.3705997i    0.4871730i    0.3922274i    0.4125934i  
    0.4019598i    0.3922274i    0.4558128i    0.4231910i  
    0.4142155i    0.4125934i    0.4231910i    0.4733096i  
 
 Modified bus impedance matrix   
 
    0.4774405i    0.3705997i    0.4019598i    0.4142155i    0.4142155i  
    0.3705997i    0.4871730i    0.3922274i    0.4125934i    0.4125934i  
    0.4019598i    0.3922274i    0.4558128i    0.4231910i    0.4231910i  
    0.4142155i    0.4125934i    0.4231910i    0.4733096i    0.4733096i  
    0.4142155i    0.4125934i    0.4231910i    0.4733096i  - 4.5266904i  
 
 Modified bus impedance matrix after eliminating fifth row and column   
 
    0.5153434i    0.4083541i    0.4406840i    0.4575258i  
    0.4083541i    0.5247796i    0.4307999i    0.4557341i  
    0.4406840i    0.4307999i    0.4953761i    0.4674398i  
    0.4575258i    0.4557341i    0.4674398i    0.5227987i  

 V4 = 1.58 /_-11.97 per unit 

 
 V4 same as found in Example 7.6