Question 890839
let {{{ theta }}} = the angle 
{{{ 180 - theta }}} = the supplement
{{{ 90 - theta }}} = the complement
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{{{ 180 - theta = 3*( 90 - theta ) + 6 }}}
{{{ 180 - theta = 270 - 3*theta ) + 6 }}}
{{{ 2*theta = 276 - 180 }}}
{{{ theta = 96/2 }}}
{{{ theta = 48 }}}
The angle is 48 degrees
check:
{{{ 180 - theta = 3*( 90 - theta ) + 6 }}}
{{{ 180 - 48 = 3*( 90 - 48 ) + 6 }}}
{{{ 132 = 3*42 + 6 }}}
{{{ 132 = 126 + 6 }}}
{{{ 132 = 132 }}}
OK