Question 33519
{{{ (x+30)+(x-55)+(x-45)+x=360  }}}
Combine like terms
{{{ x+x+x+x+30-55-45=360  }}}
{{{ 4x-70=360  }}}
Add 70 to both sides
{{{ 4x = 430 }}}
{{{ x = 430/4 }}}
I reduced the improper fraction to make it easier to work.
{{{ x = 215/2 }}}

CHECK:
{{{ x+x+x+x+30-55-45=360  }}}
Use this to plug back in
{{{ (215/2)+(215/2)+(215/2)+(215/2)+30-55-45=360  }}}
Add the fractions
{{{ (860/2)+30-55-45=360 }}}
Reduce the fraction
{{{ 430+30-55-45=360 }}}
Add and subtract left to right
{{{ 460-55-45=360 }}}
{{{ 405-45=360 }}}
{{{ 360=360 }}}
YES!!!

 So X DOES = 215/2  or  107.5 degrees