Question 698954
{{{ ( x - 3 )^2 = 25 }}}
{{{ x^2 - 6x + 9 = 25 }}}
{{{ x^2 - 6x - 16 = 0 }}}
{{{x = ( -b +- sqrt( b^2 - 4*a*c )) / (2*a) }}}
{{{ a = 1 }}}
{{{ b = -6 }}}
{{{ c = -16 }}}
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{{{ x = ( -(-6) +- sqrt( (-6)^2 - 4*1*(-16))) / (2*1) }}}
{{{ x = ( 6 +- sqrt( 36 + 64 )) / 2 }}}
{{{ x = ( 6 +- sqrt( 100 )) / 2 }}}
{{{ x = ( 6 + 10 ) / 2 }}}
{{{ x = 16/2 }}}
{{{ x = 8 }}}
and, taking the negative square root of  {{{ 100 }}}
{{{ x = ( 6 - 10 ) / 2 }}}
{{{ x = -4/2 }}}
{{{ x = -2 }}}
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check answers:
{{{ ( x - 3 )^2 = 25 }}}
{{{ ( 8 - 3 )^2 = 25 }}} 
{{{ 5^2 = 25 }}}
{{{ 25 = 25 }}}
and
{{{ ( -2 - 3 )^2 = 25 }}}
{{{ (-5)^2 = 25 }}}
{{{ 25 = 25 }}}
OK