Question 207259
the question is:  solve the quadratic equation by completing the square: 
<pre><font size = 4 color = "indigo"><b>
You did it right but your notation is bad.

{{{x^2-20x=0}}}

{{{x^2-20x+(20/2)^2 = (20/2)^2}}}

{{{x^2-20x+10^2) = (10)^2}}}

{{{x^2-20x+100) = 100}}}

{{{(x-10)(x-10) = 100}}}

{{{(x-10)^2 = 100}}}

{{{sqrt((x-10)^2)= ""+-sqrt(100)}}}

{{{x-10}}}=±{{{10}}}

Using the +

{{{x-10=10}}}
{{{x=20}}}

Using the -

{{{x-10=-10}}}
{{{x=0}}}

Edwin</pre>