Angle bisector theorem BD/DC = AB/AC: find a side or segment
This type of question, asked 5 times: CDS 2 2020, CDS 1 2022, CDS 1 2025, CDS 1 2026, CDS 2 2026. All 7 questions below, oldest first.
Try each one first, then open its answer.
Question 1
CDS 2 2020
62In a , AC = 12 cm, AB = 16 cm and AD is the bisector of . If BD = 4 cm, then what is DC equal to ?Tap an option to check your answer.
Question 2
CDS 1 2022
87In a triangle , is the bisector of . If cm, cm and cm, then what is the perimeter of the triangle?Tap an option to check your answer.
Question 3
CDS 1 2022
81In a triangle , cm, cm and is the bisector of . If cm, then what is equal to?Tap an option to check your answer.
Question 4
CDS 1 2025
14In a triangle ABC, AB = 2 cm, BC = 4 cm and AC = 3 cm. The bisector of angle A meets BC at D and the bisector of angle B meets AD at E. What is AE : ED equal to ?Tap an option to check your answer.
Question 5
CDS 1 2025
15In a triangle ABC, the bisector of angle A cuts BC at D. If AB + AC = 10 cm and BD : DC = 3 : 1, then what is the length of AC ?Tap an option to check your answer.
Question 6
CDS 1 2026
68In a triangle ABC, AB = 18 cm, BC = 22 cm and AC = 15 cm. The bisector of intersects BC at D. What is (BD DC) equal to ?Tap an option to check your answer.
Question 7
CDS 2 2026
74In a triangle ABC, AD is the bisector of angle A that meets BC at D. If AB = 21 cm, DC = 20 cm and AB : AC = 3 : 4, then what is equal to ?Tap an option to check your answer.