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MathsAges 13-15

Area of a triangle

Calculate the area of a triangle from its base and perpendicular height using A = ½bh. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 13-15

Area of a triangle

Take your time. Show your thinking.

  1. 1. A triangle has base 18 cm and perpendicular height 3 cm. Find its area.

    18 cm · 3 cm · Area of a triangle
  2. 2. A triangle has base 8 cm and perpendicular height 18 cm. Find its area.

    8 cm · 18 cm · Area of a triangle
  3. 3. A triangle has base 30 cm and perpendicular height 3 cm. Find its area.

    30 cm · 3 cm · Area of a triangle
  4. 4. A triangle has base 6 cm and perpendicular height 11 cm. Find its area.

    6 cm · 11 cm · Area of a triangle
  5. 5. A triangle has base 30 cm and perpendicular height 16 cm. Find its area.

    30 cm · 16 cm · Area of a triangle
  6. 6. A triangle has base 10 cm and perpendicular height 18 cm. Find its area.

    10 cm · 18 cm · Area of a triangle
  7. 7. A triangle has base 22 cm and perpendicular height 8 cm. Find its area.

    22 cm · 8 cm · Area of a triangle
  8. 8. A triangle has base 28 cm and perpendicular height 2 cm. Find its area.

    28 cm · 2 cm · Area of a triangle
  9. 9. A triangle has base 30 cm and perpendicular height 15 cm. Find its area.

    30 cm · 15 cm · Area of a triangle
  10. 10. A triangle has base 4 cm and perpendicular height 8 cm. Find its area.

    4 cm · 8 cm · Area of a triangle
  11. 11. A triangle has base 8 cm and perpendicular height 7 cm. Find its area.

    8 cm · 7 cm · Area of a triangle
  12. 12. A triangle has base 32 cm and perpendicular height 15 cm. Find its area.

    32 cm · 15 cm · Area of a triangle
12 questions · Seed 104729 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 13-15

Area of a triangle

Answers and reasoning. Review before teaching.

  1. 1. A triangle has base 18 cm and perpendicular height 3 cm. Find its area.

    27 cm²

    Area = ½ × base × height = ½ × 18 × 3 = 27 cm².

  2. 2. A triangle has base 8 cm and perpendicular height 18 cm. Find its area.

    72 cm²

    Area = ½ × base × height = ½ × 8 × 18 = 72 cm².

  3. 3. A triangle has base 30 cm and perpendicular height 3 cm. Find its area.

    45 cm²

    Area = ½ × base × height = ½ × 30 × 3 = 45 cm².

  4. 4. A triangle has base 6 cm and perpendicular height 11 cm. Find its area.

    33 cm²

    Area = ½ × base × height = ½ × 6 × 11 = 33 cm².

  5. 5. A triangle has base 30 cm and perpendicular height 16 cm. Find its area.

    240 cm²

    Area = ½ × base × height = ½ × 30 × 16 = 240 cm².

  6. 6. A triangle has base 10 cm and perpendicular height 18 cm. Find its area.

    90 cm²

    Area = ½ × base × height = ½ × 10 × 18 = 90 cm².

  7. 7. A triangle has base 22 cm and perpendicular height 8 cm. Find its area.

    88 cm²

    Area = ½ × base × height = ½ × 22 × 8 = 88 cm².

  8. 8. A triangle has base 28 cm and perpendicular height 2 cm. Find its area.

    28 cm²

    Area = ½ × base × height = ½ × 28 × 2 = 28 cm².

  9. 9. A triangle has base 30 cm and perpendicular height 15 cm. Find its area.

    225 cm²

    Area = ½ × base × height = ½ × 30 × 15 = 225 cm².

  10. 10. A triangle has base 4 cm and perpendicular height 8 cm. Find its area.

    16 cm²

    Area = ½ × base × height = ½ × 4 × 8 = 16 cm².

  11. 11. A triangle has base 8 cm and perpendicular height 7 cm. Find its area.

    28 cm²

    Area = ½ × base × height = ½ × 8 × 7 = 28 cm².

  12. 12. A triangle has base 32 cm and perpendicular height 15 cm. Find its area.

    240 cm²

    Area = ½ × base × height = ½ × 32 × 15 = 240 cm².

12 questions · Seed 104729 · Age guidance, not curriculum certification