Question 812968
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
how do you solve the equation by completing the square. 
z^2+5z-6=0  
First add and subtract {{{(5/2)^2}}}
z^2+5z + 25/4 -25/4 -6 = 0 
{{{(z + 5/2)^2 - 49/4 = 0}}}
{{{(z + 5/2)^2 = 49/4 }}}
    z + 5/2 = ± 7/2
    z =  -5/2 ± 7/2
 z = -6, 1