The measure are
.
Apply law of cosines to determine c.
\
(Substitute
)



Take square root each side.
\

Find A
\
(Apply Law of sines)
(Substitute
)

Apply Cross multiplication
then
.
\ \

Divide each side by 11.5.
\

Apply inverse function.
\

The sum of the angle measures of a triangle is
.
(Substitute
)
Subtract 82 from each side.
\

The value of
,
,
.