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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 16 cm and perpendicular height 5 cm. Find its area.

    16 cm · 5 cm · Area of a triangle
  2. 2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.

    12 cm · 7 cm · Area of a triangle
  3. 3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.

    20 cm · 15 cm · Area of a triangle
  4. 4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.

    24 cm · 6 cm · Area of a triangle
  5. 5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.

    20 cm · 14 cm · Area of a triangle
  6. 6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.

    4 cm · 9 cm · Area of a triangle
  7. 7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.

    30 cm · 4 cm · Area of a triangle
  8. 8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.

    16 cm · 14 cm · Area of a triangle
  9. 9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.

    20 cm · 12 cm · Area of a triangle
  10. 10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.

    18 cm · 15 cm · Area of a triangle
  11. 11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.

    16 cm · 2 cm · Area of a triangle
  12. 12. A triangle has base 14 cm and perpendicular height 2 cm. Find its area.

    14 cm · 2 cm · Area of a triangle
12 questions · Seed 66 · 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 16 cm and perpendicular height 5 cm. Find its area.

    40 cm²

    Area = ½ × base × height = ½ × 16 × 5 = 40 cm².

  2. 2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.

    42 cm²

    Area = ½ × base × height = ½ × 12 × 7 = 42 cm².

  3. 3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.

    150 cm²

    Area = ½ × base × height = ½ × 20 × 15 = 150 cm².

  4. 4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.

    72 cm²

    Area = ½ × base × height = ½ × 24 × 6 = 72 cm².

  5. 5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.

    140 cm²

    Area = ½ × base × height = ½ × 20 × 14 = 140 cm².

  6. 6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.

    18 cm²

    Area = ½ × base × height = ½ × 4 × 9 = 18 cm².

  7. 7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.

    60 cm²

    Area = ½ × base × height = ½ × 30 × 4 = 60 cm².

  8. 8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.

    112 cm²

    Area = ½ × base × height = ½ × 16 × 14 = 112 cm².

  9. 9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.

    120 cm²

    Area = ½ × base × height = ½ × 20 × 12 = 120 cm².

  10. 10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.

    135 cm²

    Area = ½ × base × height = ½ × 18 × 15 = 135 cm².

  11. 11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.

    16 cm²

    Area = ½ × base × height = ½ × 16 × 2 = 16 cm².

  12. 12. A triangle has base 14 cm and perpendicular height 2 cm. Find its area.

    14 cm²

    Area = ½ × base × height = ½ × 14 × 2 = 14 cm².

12 questions · Seed 66 · Age guidance, not curriculum certification