Question 557161
Supplementary means they add up to 180 degrees
{{{ ( 10c - 20 ) + ( 5c + 12 ) = 180 }}}
{{{ 10c - 20 + 5c + 12 = 180 }}}
{{{ 15c - 8 = 180 }}}
{{{ 15c = 188 }}}
{{{ c = 12.5333 }}}
The 2 angles are:
{{{ 10c - 20 = 125.333 - 20 }}}
{{{ 10c - 20 = 105.333 }}}
and
{{{ 5c + 12 = 62.666 + 12 }}}
{{{ 5c + 12 = 74.666 }}}
The angles are 105 + 1/3
and 74 + 2/3
which add up to 180