CBSE Class 10 Mathematics Basic 2026: question 8
Set in the CBSE Class 10 board exam of 2026, paper 430/2/1, section A, question 8, for 1 mark. Try it first; the hints and our step-by-step solution are below.
Q8 · 1 mark · MCQTriangles
In the given figure, if , cm, cm and cm, the length of AC is :
- (A)1.5 cm
- (B)3 cm
- (C)3.5 cm
- (D)4.5 cm
Figure in the paper: Triangle ABC with D on side AB and E on side AC, DE parallel to BC. Marked: AD = 1.5 cm, DB = 3 cm (along side AB), EC = 2 cm (along side AC). See it in the official paper.
Source: official question paper from cbse.gov.in (PDF). See it in the full 2026 board paper, set 430/2/1.
Hints
Open one hint at a time and try again before the next.
Hint 1
Which theorem relates the segments cut on two sides of a triangle by a line parallel to the third side?
Hint 2
Use AD/DB = AE/EC to find AE first.
Hint 3
AE = 2 × (1.5/3) = 1 cm; now add EC to get AC.
Step-by-step solution
Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.
- ½ mark
Since , by the Basic Proportionality Theorem: , so cm.
- ½ mark
cm. Hence option (B).
Answer: AC = 3 cm, option (B)
Where the marks are
- Applies BPT to get AE = 1 cm and AC = AE + EC = 3 cm, choosing option (B) (1 mark)
Revise the chapter
- Chapter: Triangles (notes, formulas, where marks are lost and every past question)
- Topic: Basic Proportionality Theorem (Thales Theorem)
More questions from Triangles
- 2026 board paper, set 430/3/1 (Basic), Q33(a) · 5 marksState and Prove "Basic Proportionality Theorem".
- 2026 board paper, set 430/4/1 (Basic), Q25 · 2 marksIn the given figure, QR ∥ CB and RP ∥ AC. If BR = 10 cm, QA = 12 cm, BP = 12 cm and PC = 18 cm, then find the …
- 2026 board paper, set 430/4/1 (Basic), Q33(a) · 5 marksIf a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, the…
The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.