Since the sum of interior angles in a triangle is always 180°, we can write the following equation:
[tex]m\angle G+m\angle H+m\angle I=180[/tex]
Now, substituting values, we have:
[tex]\begin{gathered} 9x-2+3x-19+3x+6=180 \\ 15x-15=180 \\ 15x=195 \\ x=13 \end{gathered}[/tex]
Now, calculating m∠G, we have:
[tex]\begin{gathered} m\angle G=9x-2 \\ =9\cdot13-2 \\ =117-2 \\ =115\degree \end{gathered}[/tex]
