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Grade 10

Grade 10 Similar Triangles Worksheet

Apply scale factors, shadow proportions, and mirror problems to find missing sides in similar triangles. Free printable worksheet — 20 questions plus a separate answer key. Each sheet is freshly generated, so your kid can practice as many times as they need.

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Sample questions

Two examples from the Similar Triangles worksheet. Print the full sheet for 20 questions plus an answer key.

  1. Sample 1
    Figure showing triangle 1 with sides 5, 12, 13 and triangle 2 with sides 10, ?, 26. Scale factor 25121310?26Scale factor 2

    Sides 5, 12, 13 and 10, 26, ?. Missing side?

    Show answer24
  2. Sample 2
    Figure showing triangle 1 with sides 8, 15, 17 and triangle 2 with sides 24, 45, ?. Scale factor 3815172445?Scale factor 3

    Sides 8, 15, 17 and 24, 45, ?. Missing side?

    Show answer51

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