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We are given two similar triangles: △LMN and △ABC, where the angles are similar, meaning their corresponding sides are in proportion.

Known lengths:

  • MN = 15 cm
  • AB = 6 cm
  • BC = 9 cm

We are asked to find:

  1. Length of LM
  2. Length of AB (given as 6 cm, perhaps a typo, so we'll confirm calculations)

Step 1: Identify corresponding sides

Since the triangles are similar by angles LMN and ABC, the corresponding vertices align as:

  • L corresponds to A
  • M corresponds to B
  • N corresponds to C

Thus, sides correspond as:

  • LM corresponds to AB
  • MN corresponds to BC
  • LN corresponds to AC

Step 2: Use the ratio of corresponding sides

The similarity ratio (scale factor) between △LMN and △ABC can be found by comparing corresponding sides:

MN / BC = 15 cm / 9 cm = 5/3

This means the side lengths in △LMN are scaled up by a factor of 5/3 compared to △ABC.

Step 3: Find LM

Because LM corresponds to AB, and ratio LM / AB = 5/3, then:

LM = (5/3) × AB = (5/3) × 6 cm = 10 cm

Step 4: Re-examine AB

Given AB is 6 cm, which matches the original data.

Therefore, no calculation is needed for AB, it is already provided.

Final answers:

  • LM = 10 cm
  • AB = 6 cm (given)

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