From the angle property of triangle :
The sum of all angles in the triangle are equal to 180 degrees.
In the given triangle DEF
[tex]\begin{gathered} \angle DEF+\angle DFE+\angle FDE=180 \\ \text{ Substitute the value of given angle:}\angle DFE=30,\text{ }\angle FDE=47 \\ \angle DEF+30+47=180 \\ \angle DEF+77=180 \\ \angle DEF=180-77 \\ \angle DEF=103^o \end{gathered}[/tex]
The value of
Answer :
