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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 13-15
Area of a triangle
Take your time. Show your thinking.
1. A triangle has base 16 cm and perpendicular height 5 cm. Find its area.
16 cm · 5 cm · Area of a triangle2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.
12 cm · 7 cm · Area of a triangle3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.
20 cm · 15 cm · Area of a triangle4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.
24 cm · 6 cm · Area of a triangle5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.
20 cm · 14 cm · Area of a triangle6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.
4 cm · 9 cm · Area of a triangle7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.
30 cm · 4 cm · Area of a triangle8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.
16 cm · 14 cm · Area of a triangle9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.
20 cm · 12 cm · Area of a triangle10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.
18 cm · 15 cm · Area of a triangle11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm · 2 cm · Area of a triangle12. 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. A triangle has base 16 cm and perpendicular height 5 cm. Find its area.
40 cm²Area = ½ × base × height = ½ × 16 × 5 = 40 cm².
2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.
42 cm²Area = ½ × base × height = ½ × 12 × 7 = 42 cm².
3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.
150 cm²Area = ½ × base × height = ½ × 20 × 15 = 150 cm².
4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.
72 cm²Area = ½ × base × height = ½ × 24 × 6 = 72 cm².
5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.
140 cm²Area = ½ × base × height = ½ × 20 × 14 = 140 cm².
6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.
18 cm²Area = ½ × base × height = ½ × 4 × 9 = 18 cm².
7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.
60 cm²Area = ½ × base × height = ½ × 30 × 4 = 60 cm².
8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.
112 cm²Area = ½ × base × height = ½ × 16 × 14 = 112 cm².
9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.
120 cm²Area = ½ × base × height = ½ × 20 × 12 = 120 cm².
10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.
135 cm²Area = ½ × base × height = ½ × 18 × 15 = 135 cm².
11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm²Area = ½ × base × height = ½ × 16 × 2 = 16 cm².
12. A triangle has base 14 cm and perpendicular height 2 cm. Find its area.
14 cm²Area = ½ × base × height = ½ × 14 × 2 = 14 cm².
12 questions · Seed 66 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 13-15
Area of a triangle
Take your time. Show your thinking.
1. A triangle has base 16 cm and perpendicular height 5 cm. Find its area.
16 cm · 5 cm · Area of a triangle2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.
12 cm · 7 cm · Area of a triangle3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.
20 cm · 15 cm · Area of a triangle4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.
24 cm · 6 cm · Area of a triangle5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.
20 cm · 14 cm · Area of a triangle6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.
4 cm · 9 cm · Area of a triangle7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.
30 cm · 4 cm · Area of a triangle8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.
16 cm · 14 cm · Area of a triangle9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.
20 cm · 12 cm · Area of a triangle10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.
18 cm · 15 cm · Area of a triangle11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm · 2 cm · Area of a triangle12. 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
Worksheet StudioAnswer key · Ages 13-15
Area of a triangle
Answers and reasoning. Review before teaching.
1. A triangle has base 16 cm and perpendicular height 5 cm. Find its area.
40 cm²Area = ½ × base × height = ½ × 16 × 5 = 40 cm².
2. A triangle has base 12 cm and perpendicular height 7 cm. Find its area.
42 cm²Area = ½ × base × height = ½ × 12 × 7 = 42 cm².
3. A triangle has base 20 cm and perpendicular height 15 cm. Find its area.
150 cm²Area = ½ × base × height = ½ × 20 × 15 = 150 cm².
4. A triangle has base 24 cm and perpendicular height 6 cm. Find its area.
72 cm²Area = ½ × base × height = ½ × 24 × 6 = 72 cm².
5. A triangle has base 20 cm and perpendicular height 14 cm. Find its area.
140 cm²Area = ½ × base × height = ½ × 20 × 14 = 140 cm².
6. A triangle has base 4 cm and perpendicular height 9 cm. Find its area.
18 cm²Area = ½ × base × height = ½ × 4 × 9 = 18 cm².
7. A triangle has base 30 cm and perpendicular height 4 cm. Find its area.
60 cm²Area = ½ × base × height = ½ × 30 × 4 = 60 cm².
8. A triangle has base 16 cm and perpendicular height 14 cm. Find its area.
112 cm²Area = ½ × base × height = ½ × 16 × 14 = 112 cm².
9. A triangle has base 20 cm and perpendicular height 12 cm. Find its area.
120 cm²Area = ½ × base × height = ½ × 20 × 12 = 120 cm².
10. A triangle has base 18 cm and perpendicular height 15 cm. Find its area.
135 cm²Area = ½ × base × height = ½ × 18 × 15 = 135 cm².
11. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm²Area = ½ × base × height = ½ × 16 × 2 = 16 cm².
12. A triangle has base 14 cm and perpendicular height 2 cm. Find its area.
14 cm²Area = ½ × base × height = ½ × 14 × 2 = 14 cm².
12 questions · Seed 66 · Age guidance, not curriculum certification