Practice30Create account

In ΔLMN and ΔXYZ it is given that ∠L = ∠Y and ∠M = ∠X. Which similarity statement writes the vertices in the correct corresponding order?

Class 10Triangles (Similarity)Geometry — Similarity
  • AΔLMN ~ ΔXYZ
  • BΔLMN ~ ΔYXZ
  • CΔLMN ~ ΔZXY
  • DΔLMN ~ ΔXZY

Step-by-Step Solution

The equal angles fix the correspondence: L ↔ Y, M ↔ X, and therefore N ↔ Z. Reading the letters in that order gives ΔLMN ~ ΔYXZ. "ΔLMN ~ ΔXYZ" is the common slip of copying the letters alphabetically instead of matching equal angles; "ΔLMN ~ ΔZXY" and "ΔLMN ~ ΔXZY" pair N with the wrong vertex.
Answer: B) ΔLMN ~ ΔYXZ

Key idea: Similarity vs congruence

**Congruent**: same shape AND same size. All corresponding parts equal.
**Similar**: same shape, possibly DIFFERENT size. Corresponding angles equal; corresponding sides PROPORTIONAL (in fixed ratio k).

If two triangles are similar with scale factor :
- Corresponding sides differ by factor .
- Corresponding angles are equal (always, by definition).
- Areas differ by factor — critical fact, and a common test question.

**Examples**:
- Equilateral triangles are ALL similar (same angles 60°-60°-60°).
- A photograph and its enlarged print are similar.
- Two right triangles sharing one acute angle are similar (AA).

Master this chapter in 30 minutes a day.

Don't just memorise the answer — build a daily practice habit.

Practice 5 Similar Questions Free →

All Triangles (Similarity) practice questions

More Class 10 Triangles (Similarity) practice

It is given that ΔABC ~ ΔQRP. Which of these equalities of ratios is correct?In trapezium ABCD, AB ∥ DC and the diagonals AC and BD cut each other at O. Which pair…In trapezium PQRS, PQ ∥ SR and the diagonals meet at O. If PQ = 12 cm, SR = 8 cm and OQ…To find the height of a brick-kiln chimney, Anjali lays a small mirror flat on the…In ΔABC, AB = 4.5 cm, BC = 6 cm and CA = 7.5 cm. In ΔDEF, DE = 6 cm, EF = 8 cm and FD =…