How do you solve the equation #x^2-2x-10=0# by completing the square?

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Answer 1 · 2017-06-06T17:46:44

#x=1+-sqrt11#

#x^2-2x-10=0#

half the coefficient of #x# square it, add and subtract to the equation

#(x^2-2x+1^2)-1^2-10=0#

The bracket is a perfect square

#=>(x-1)^2-11=0#

#(x-1)^2=11#

#x-1=+-sqrt11#

#x=1+-sqrt11#