Question 992982

a square have same sides: 
{{{x^2 + x =x^2 + 4}}}

{{{cross(x^2) + x =cross(x^2) + 4}}}

{{{x = 4}}}

sides are:
{{{x^2 + x=4^2+4=16+4=20}}}
{{{x^2 + 4=4^2+4=16+4=20}}}


a hexagon: all sides are equal 

{{{x^2 + 3x= x^2 + x + 2}}}

{{{cross(x^2) + 3x= cross(x^2) + x + 2}}}

{{{3x=  x + 2}}}

{{{3x-x= 2}}}

{{{2x= 2}}}

{{{x= 2/2}}}

{{{x= 1}}}

check:

{{{x^2 + 3x=1^2+3*1=1+3=4}}}
{{{ x^2 + x + 2=1^2+1+2=4}}}