Question 725129
{{{ 2*( x - 3 )^2 - 50 = 0 }}}
{{{ 2*( x^2 - 6x + 9 ) - 50 = 0 }}}
{{{ 2x^2 - 12x + 18 - 50 = 0 }}}
{{{ 2x^2 - 12x - 32 = 0 }}}
{{{ x^2 - 6x - 16 = 0 }}}
You can complete the square
{{{ x^2 - 6x  = 16 }}}
{{{ x^2 - 6x + ( -6/2)^2 = 16 + (-6/2 )^2 }}}
{{{ x^2 - 6x + 9 = 16 + 9 }}}
{{{ ( x - 3 )^2 = 5^2 }}}
{{{ x - 3 = 5 }}}
{{{ x = 8 }}}
and, also,
{{{ x - 3 = -5 }}}
{{{ x = -2 }}}
------------
check answers:
{{{ x = 8 }}}
{{{ 2*( x - 3 )^2 - 50 = 0 }}}
{{{ 2*( 8 - 3 )^2 - 50 = 0 }}}
{{{ 2*25 - 50 = 0 }}}
{{{ 50 - 50 = 0 }}}
{{{ 0 = 0 }}}
and
{{{ x = -2 }}}
{{{ 2*( -2 - 3 )^2 - 50 = 0 }}}
{{{ 2*25 - 50 = 0 }}}
{{{ 50 - 50 = 0 }}}
{{{ 0=0 }}}
OK