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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.
Worksheet StudioPractice pack · Ages 10-12
Area of a triangle
Take your time. Show your thinking.
1. A triangle has base 4 cm and perpendicular height 10 cm. Find its area.
4 cm · 10 cm · Area of a triangle2. A triangle has base 12 cm and perpendicular height 3 cm. Find its area.
12 cm · 3 cm · Area of a triangle3. A triangle has base 32 cm and perpendicular height 14 cm. Find its area.
32 cm · 14 cm · Area of a triangle4. A triangle has base 24 cm and perpendicular height 2 cm. Find its area.
24 cm · 2 cm · Area of a triangle5. A triangle has base 22 cm and perpendicular height 6 cm. Find its area.
22 cm · 6 cm · Area of a triangle6. A triangle has base 20 cm and perpendicular height 6 cm. Find its area.
20 cm · 6 cm · Area of a triangle7. A triangle has base 10 cm and perpendicular height 16 cm. Find its area.
10 cm · 16 cm · Area of a triangle8. A triangle has base 24 cm and perpendicular height 4 cm. Find its area.
24 cm · 4 cm · Area of a triangle9. A triangle has base 28 cm and perpendicular height 15 cm. Find its area.
28 cm · 15 cm · Area of a triangle10. A triangle has base 24 cm and perpendicular height 15 cm. Find its area.
24 cm · 15 cm · Area of a triangle11. A triangle has base 26 cm and perpendicular height 18 cm. Find its area.
26 cm · 18 cm · Area of a triangle12. A triangle has base 32 cm and perpendicular height 11 cm. Find its area.
32 cm · 11 cm · Area of a triangle
12 questions · Seed 42 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12
Area of a triangle
Answers and reasoning. Review before teaching.
1. A triangle has base 4 cm and perpendicular height 10 cm. Find its area.
20 cm²Area = ½ × base × height = ½ × 4 × 10 = 20 cm².
2. A triangle has base 12 cm and perpendicular height 3 cm. Find its area.
18 cm²Area = ½ × base × height = ½ × 12 × 3 = 18 cm².
3. A triangle has base 32 cm and perpendicular height 14 cm. Find its area.
224 cm²Area = ½ × base × height = ½ × 32 × 14 = 224 cm².
4. A triangle has base 24 cm and perpendicular height 2 cm. Find its area.
24 cm²Area = ½ × base × height = ½ × 24 × 2 = 24 cm².
5. A triangle has base 22 cm and perpendicular height 6 cm. Find its area.
66 cm²Area = ½ × base × height = ½ × 22 × 6 = 66 cm².
6. A triangle has base 20 cm and perpendicular height 6 cm. Find its area.
60 cm²Area = ½ × base × height = ½ × 20 × 6 = 60 cm².
7. A triangle has base 10 cm and perpendicular height 16 cm. Find its area.
80 cm²Area = ½ × base × height = ½ × 10 × 16 = 80 cm².
8. A triangle has base 24 cm and perpendicular height 4 cm. Find its area.
48 cm²Area = ½ × base × height = ½ × 24 × 4 = 48 cm².
9. A triangle has base 28 cm and perpendicular height 15 cm. Find its area.
210 cm²Area = ½ × base × height = ½ × 28 × 15 = 210 cm².
10. A triangle has base 24 cm and perpendicular height 15 cm. Find its area.
180 cm²Area = ½ × base × height = ½ × 24 × 15 = 180 cm².
11. A triangle has base 26 cm and perpendicular height 18 cm. Find its area.
234 cm²Area = ½ × base × height = ½ × 26 × 18 = 234 cm².
12. A triangle has base 32 cm and perpendicular height 11 cm. Find its area.
176 cm²Area = ½ × base × height = ½ × 32 × 11 = 176 cm².
12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12
Area of a triangle
Take your time. Show your thinking.
1. A triangle has base 4 cm and perpendicular height 10 cm. Find its area.
4 cm · 10 cm · Area of a triangle2. A triangle has base 12 cm and perpendicular height 3 cm. Find its area.
12 cm · 3 cm · Area of a triangle3. A triangle has base 32 cm and perpendicular height 14 cm. Find its area.
32 cm · 14 cm · Area of a triangle4. A triangle has base 24 cm and perpendicular height 2 cm. Find its area.
24 cm · 2 cm · Area of a triangle5. A triangle has base 22 cm and perpendicular height 6 cm. Find its area.
22 cm · 6 cm · Area of a triangle6. A triangle has base 20 cm and perpendicular height 6 cm. Find its area.
20 cm · 6 cm · Area of a triangle7. A triangle has base 10 cm and perpendicular height 16 cm. Find its area.
10 cm · 16 cm · Area of a triangle8. A triangle has base 24 cm and perpendicular height 4 cm. Find its area.
24 cm · 4 cm · Area of a triangle9. A triangle has base 28 cm and perpendicular height 15 cm. Find its area.
28 cm · 15 cm · Area of a triangle10. A triangle has base 24 cm and perpendicular height 15 cm. Find its area.
24 cm · 15 cm · Area of a triangle11. A triangle has base 26 cm and perpendicular height 18 cm. Find its area.
26 cm · 18 cm · Area of a triangle12. A triangle has base 32 cm and perpendicular height 11 cm. Find its area.
32 cm · 11 cm · Area of a triangle
12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12
Area of a triangle
Answers and reasoning. Review before teaching.
1. A triangle has base 4 cm and perpendicular height 10 cm. Find its area.
20 cm²Area = ½ × base × height = ½ × 4 × 10 = 20 cm².
2. A triangle has base 12 cm and perpendicular height 3 cm. Find its area.
18 cm²Area = ½ × base × height = ½ × 12 × 3 = 18 cm².
3. A triangle has base 32 cm and perpendicular height 14 cm. Find its area.
224 cm²Area = ½ × base × height = ½ × 32 × 14 = 224 cm².
4. A triangle has base 24 cm and perpendicular height 2 cm. Find its area.
24 cm²Area = ½ × base × height = ½ × 24 × 2 = 24 cm².
5. A triangle has base 22 cm and perpendicular height 6 cm. Find its area.
66 cm²Area = ½ × base × height = ½ × 22 × 6 = 66 cm².
6. A triangle has base 20 cm and perpendicular height 6 cm. Find its area.
60 cm²Area = ½ × base × height = ½ × 20 × 6 = 60 cm².
7. A triangle has base 10 cm and perpendicular height 16 cm. Find its area.
80 cm²Area = ½ × base × height = ½ × 10 × 16 = 80 cm².
8. A triangle has base 24 cm and perpendicular height 4 cm. Find its area.
48 cm²Area = ½ × base × height = ½ × 24 × 4 = 48 cm².
9. A triangle has base 28 cm and perpendicular height 15 cm. Find its area.
210 cm²Area = ½ × base × height = ½ × 28 × 15 = 210 cm².
10. A triangle has base 24 cm and perpendicular height 15 cm. Find its area.
180 cm²Area = ½ × base × height = ½ × 24 × 15 = 180 cm².
11. A triangle has base 26 cm and perpendicular height 18 cm. Find its area.
234 cm²Area = ½ × base × height = ½ × 26 × 18 = 234 cm².
12. A triangle has base 32 cm and perpendicular height 11 cm. Find its area.
176 cm²Area = ½ × base × height = ½ × 32 × 11 = 176 cm².
12 questions · Seed 42 · Age guidance, not curriculum certification