Answer:
m∠ABG = 20 degrees
m∠BCA = 22 degrees
m∠BAC = 118 degrees
m∠BAG = 59 degrees
DG = 4
BE = 12.4
BG = 11.7
GC = 20.4
Step-by-step explanation:
The given parameters are;
m∠CBG = 20°, m∠BCG = 11°
The incenter of a triangle is the point where the three bisectors of ΔABC meets
m∠ABG = m∠CBG = 20° by definition of angle bisector
m∠ABG = 20°
m∠ACG = m∠BCG = 11° by definition of angle bisector
m∠BCA = m∠ACG + m∠BCG = 11° + 11° = 22°
m∠ABC = m∠ABG + m∠CBG = 20° + 20° = 40°
m∠BAC = 180° - (m∠BCA+m∠ABC) = 180° - (40° + 22°) = 118°
m∠BAG = m∠CAG by definition of angle bisector
m∠BAC = 118° = m∠BAG + m∠CAG = m∠BAG + m∠BAG = 2 × m∠BAG
2 × mBAG = 118°
m∠BAG = 118°/2 = 59°
m∠BAG = 59°
Given that "G" is the incenter of the triangle ABC, we have;
GF = GE = DG = The radius of the incircle of the triangle = 4
Therefore, by Pythagoras' theorem, we have;
BG = √(11² + 4²) = √137 ≈ 11.7
BE = √((BG)² + 4²) = √(137 + 4²) = √153 ≈ 12.4
GC = √(20² + 4²) = √416= 4·√26 ≈ 20.4
