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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 32 cm and perpendicular height 5 cm. Find its area.
32 cm · 5 cm · Area of a triangle2. A triangle has base 18 cm and perpendicular height 11 cm. Find its area.
18 cm · 11 cm · Area of a triangle3. A triangle has base 28 cm and perpendicular height 10 cm. Find its area.
28 cm · 10 cm · Area of a triangle4. A triangle has base 26 cm and perpendicular height 12 cm. Find its area.
26 cm · 12 cm · Area of a triangle5. A triangle has base 24 cm and perpendicular height 9 cm. Find its area.
24 cm · 9 cm · Area of a triangle6. A triangle has base 18 cm and perpendicular height 6 cm. Find its area.
18 cm · 6 cm · Area of a triangle7. A triangle has base 20 cm and perpendicular height 9 cm. Find its area.
20 cm · 9 cm · Area of a triangle8. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm · 2 cm · Area of a triangle9. A triangle has base 32 cm and perpendicular height 8 cm. Find its area.
32 cm · 8 cm · Area of a triangle10. A triangle has base 10 cm and perpendicular height 17 cm. Find its area.
10 cm · 17 cm · Area of a triangle11. A triangle has base 20 cm and perpendicular height 5 cm. Find its area.
20 cm · 5 cm · Area of a triangle12. A triangle has base 12 cm and perpendicular height 4 cm. Find its area.
12 cm · 4 cm · Area of a triangle
12 questions · Seed 67 · 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 32 cm and perpendicular height 5 cm. Find its area.
80 cm²Area = ½ × base × height = ½ × 32 × 5 = 80 cm².
2. A triangle has base 18 cm and perpendicular height 11 cm. Find its area.
99 cm²Area = ½ × base × height = ½ × 18 × 11 = 99 cm².
3. A triangle has base 28 cm and perpendicular height 10 cm. Find its area.
140 cm²Area = ½ × base × height = ½ × 28 × 10 = 140 cm².
4. A triangle has base 26 cm and perpendicular height 12 cm. Find its area.
156 cm²Area = ½ × base × height = ½ × 26 × 12 = 156 cm².
5. A triangle has base 24 cm and perpendicular height 9 cm. Find its area.
108 cm²Area = ½ × base × height = ½ × 24 × 9 = 108 cm².
6. A triangle has base 18 cm and perpendicular height 6 cm. Find its area.
54 cm²Area = ½ × base × height = ½ × 18 × 6 = 54 cm².
7. A triangle has base 20 cm and perpendicular height 9 cm. Find its area.
90 cm²Area = ½ × base × height = ½ × 20 × 9 = 90 cm².
8. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm²Area = ½ × base × height = ½ × 16 × 2 = 16 cm².
9. A triangle has base 32 cm and perpendicular height 8 cm. Find its area.
128 cm²Area = ½ × base × height = ½ × 32 × 8 = 128 cm².
10. A triangle has base 10 cm and perpendicular height 17 cm. Find its area.
85 cm²Area = ½ × base × height = ½ × 10 × 17 = 85 cm².
11. A triangle has base 20 cm and perpendicular height 5 cm. Find its area.
50 cm²Area = ½ × base × height = ½ × 20 × 5 = 50 cm².
12. A triangle has base 12 cm and perpendicular height 4 cm. Find its area.
24 cm²Area = ½ × base × height = ½ × 12 × 4 = 24 cm².
12 questions · Seed 67 · 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 32 cm and perpendicular height 5 cm. Find its area.
32 cm · 5 cm · Area of a triangle2. A triangle has base 18 cm and perpendicular height 11 cm. Find its area.
18 cm · 11 cm · Area of a triangle3. A triangle has base 28 cm and perpendicular height 10 cm. Find its area.
28 cm · 10 cm · Area of a triangle4. A triangle has base 26 cm and perpendicular height 12 cm. Find its area.
26 cm · 12 cm · Area of a triangle5. A triangle has base 24 cm and perpendicular height 9 cm. Find its area.
24 cm · 9 cm · Area of a triangle6. A triangle has base 18 cm and perpendicular height 6 cm. Find its area.
18 cm · 6 cm · Area of a triangle7. A triangle has base 20 cm and perpendicular height 9 cm. Find its area.
20 cm · 9 cm · Area of a triangle8. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm · 2 cm · Area of a triangle9. A triangle has base 32 cm and perpendicular height 8 cm. Find its area.
32 cm · 8 cm · Area of a triangle10. A triangle has base 10 cm and perpendicular height 17 cm. Find its area.
10 cm · 17 cm · Area of a triangle11. A triangle has base 20 cm and perpendicular height 5 cm. Find its area.
20 cm · 5 cm · Area of a triangle12. A triangle has base 12 cm and perpendicular height 4 cm. Find its area.
12 cm · 4 cm · Area of a triangle
12 questions · Seed 67 · 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 32 cm and perpendicular height 5 cm. Find its area.
80 cm²Area = ½ × base × height = ½ × 32 × 5 = 80 cm².
2. A triangle has base 18 cm and perpendicular height 11 cm. Find its area.
99 cm²Area = ½ × base × height = ½ × 18 × 11 = 99 cm².
3. A triangle has base 28 cm and perpendicular height 10 cm. Find its area.
140 cm²Area = ½ × base × height = ½ × 28 × 10 = 140 cm².
4. A triangle has base 26 cm and perpendicular height 12 cm. Find its area.
156 cm²Area = ½ × base × height = ½ × 26 × 12 = 156 cm².
5. A triangle has base 24 cm and perpendicular height 9 cm. Find its area.
108 cm²Area = ½ × base × height = ½ × 24 × 9 = 108 cm².
6. A triangle has base 18 cm and perpendicular height 6 cm. Find its area.
54 cm²Area = ½ × base × height = ½ × 18 × 6 = 54 cm².
7. A triangle has base 20 cm and perpendicular height 9 cm. Find its area.
90 cm²Area = ½ × base × height = ½ × 20 × 9 = 90 cm².
8. A triangle has base 16 cm and perpendicular height 2 cm. Find its area.
16 cm²Area = ½ × base × height = ½ × 16 × 2 = 16 cm².
9. A triangle has base 32 cm and perpendicular height 8 cm. Find its area.
128 cm²Area = ½ × base × height = ½ × 32 × 8 = 128 cm².
10. A triangle has base 10 cm and perpendicular height 17 cm. Find its area.
85 cm²Area = ½ × base × height = ½ × 10 × 17 = 85 cm².
11. A triangle has base 20 cm and perpendicular height 5 cm. Find its area.
50 cm²Area = ½ × base × height = ½ × 20 × 5 = 50 cm².
12. A triangle has base 12 cm and perpendicular height 4 cm. Find its area.
24 cm²Area = ½ × base × height = ½ × 12 × 4 = 24 cm².
12 questions · Seed 67 · Age guidance, not curriculum certification