Parallelogram and trapezoid area
Calculate the area of parallelograms and trapezoids.
Practice + answer key · 4 pages
Worksheet settings8 questions · 2 columns · A4
Geometry
What you’ll practice
Choose the correct area rule for a parallelogram or trapezoid.
For a parallelogram, multiply the base by the perpendicular height. For a trapezoid, find the average of the two parallel bases first, then multiply by the height.
How this skill works
Parallelogram area is base × height. A slanted side is not a replacement for the perpendicular height.
Trapezoid area is (base 1 + base 2) × height ÷ 2. The two bases must be the parallel sides.
Worked example
- Average the bases: (6 + 10) ÷ 2 = 8 cm.
- Multiply by the height: 8 × 4 = 32 cm².
Answer: 32 cm²
Teaching notes
- The dashed height and right-angle marker identify the perpendicular measurement.
Practice questions
- Find the area of the trapezoid.
Trapezoid with parallel bases 8 cm and 10 cm, and perpendicular height 4 cm.
- Find the area of the parallelogram.
Parallelogram with base 10 cm and perpendicular height 12 cm.
- Find the area of the parallelogram.
Parallelogram with base 7 cm and perpendicular height 3 cm.
- Find the area of the parallelogram.
Parallelogram with base 9 cm and perpendicular height 3 cm.
- Find the area of the trapezoid.
Trapezoid with parallel bases 12 cm and 5 cm, and perpendicular height 5 cm.
- Find the area of the trapezoid.
Trapezoid with parallel bases 6 cm and 7 cm, and perpendicular height 3 cm.
- Find the area of the trapezoid.
Trapezoid with parallel bases 3 cm and 4 cm, and perpendicular height 3 cm.
- Find the area of the trapezoid.
Trapezoid with parallel bases 9 cm and 11 cm, and perpendicular height 11 cm.
Answers and steps
- 36 cm²
- Area = (8 + 10) × 4 ÷ 2 = 36 cm².
- 120 cm²
- Area = base × perpendicular height = 10 × 12 = 120 cm².
- 21 cm²
- Area = base × perpendicular height = 7 × 3 = 21 cm².
- 27 cm²
- Area = base × perpendicular height = 9 × 3 = 27 cm².
- 42.5 cm²
- Area = (12 + 5) × 5 ÷ 2 = 42.5 cm².
- 19.5 cm²
- Area = (6 + 7) × 3 ÷ 2 = 19.5 cm².
- 10.5 cm²
- Area = (3 + 4) × 3 ÷ 2 = 10.5 cm².
- 110 cm²
- Area = (9 + 11) × 11 ÷ 2 = 110 cm².