Question 433865
You have 
{{{x = sqrt(4) }}}
and 
{{{x = -3/4 }}}
Note that 
{{{ sqrt(4) = 2 }}}
and
{{{ sqrt(4) = -2 }}}
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These can be written as:
{{{ x - 2 = 0}}}
{{{ x + 2 = 0 }}}
{{{ x + 3/4 = 0 }}}
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This is a 3rd degree equation
{{{ ( x - 2 )*( x + 2 )*( x + 3/4 ) = 0 }}}
{{{ ( x^2 - 4) * (x + 3/4 ) }}}
{{{ x^3 + (3/4)*x^2 - 4x - 3 = 0 }}}
{{{ 4x^3 + 3x^2 - 16x - 12 = 0 }}}
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Checking for {{{ x = -2 }}}
{{{ 4(-2)^3 + 3*(-2)^2 - 16*(-2) - 12 = 0 }}}
{{{ -32 + 12 + 32 - 12 = 0 }}}
{{{ 0 = 0 }}}
You can check 
{{{ x = 2 }}} and
{{{ x = -3/4 }}}