m∠HDG = 28°, m∠EFG = 50°, m∠DEG = 67°, m∠DGE = 65°
Solution:
Triangle sum property:
Sum of the angles of the triangle = 180°
In ΔDHG,
m∠HDG + 120° + 32° = 180°
m∠HDG + 152° = 180°
m∠HDG = 180° – 152°
m∠HDG = 28°
In ΔGEF,
m∠EFG + 17° + 113° = 180°
m∠EFG + 130° = 180°
m∠EFG = 180° – 130°
m∠EFG = 50°
Sum of the adjacent angles in a straight line is 180°
m∠DEG + m∠DEF = 180°
m∠DEG + 113° = 180°
m∠DEG = 180° – 113°
m∠DEG = 67°
In ΔDGE,
m∠DGE + 48° + 67° = 180°
m∠DGE + 115° = 180°
m∠DGE = 180° – 115°
m∠DGE = 65°
Hence m∠HDG = 28°, m∠EFG = 50°, m∠DEG = 67°, m∠DGE = 65°.
