Revision Notes for Class 8 Maths Chapter 14: Area

Condensed revision notes for Class 8 Maths Chapter 14: Area – Ganita Prakash textbook (the final Class 8 Maths chapter). These Class 8 Mathematics Chapter 14 notes are ideal for quick revision just before exams.

• Rectangle: Area = length × breadth. Square: Area = side².
• Triangle: Area = ½ × base × height.
• Parallelogram: Area = base × height (uses perpendicular height, not the slant side).
• Rhombus: Area = ½ × d₁ × d₂ (product of diagonals, halved).
• Trapezium: Area = ½ × (sum of parallel sides) × height.
• Regular hexagon: Area = (3√3/2) × side².
• Equilateral triangle: Area = (√3/4) × side².
• Scaling rule: if every linear dimension of a shape is scaled by k, its area scales by k² (e.g. doubling a square’s side quadruples its area).
• Path/border area: Area of path = Outer area − Inner area. For a uniform border of width d around an l×w rectangle: Area = 2d(l+w) + 4d².
• Crosspath area: Area = (horizontal strip) + (vertical strip) − (overlap square), to avoid double-counting the overlap.
• Midpoint triangle theorem: joining the midpoints of two sides of a triangle creates a smaller triangle with ¼ the area of the original.
• Varignon parallelogram: joining the midpoints of any quadrilateral’s four sides forms a parallelogram with exactly half the original quadrilateral’s area.
• Unit conversions: 1 in = 2.54 cm; 1 ft² = 144 in²; 1 km² = 1,000,000 m².

More on this chapter: NCERT Solutions for Class 8 Maths Chapter 14 | Extra Questions for Class 8 Maths Chapter 14 | Class 8 Maths Book | Formulas Handbook

Written by Satish

NCERTBooks.org is an independent educational resource run by a small team focused on making official NCERT textbooks easy to find, read, and download for students, parents, and teachers across India. We are not affiliated with NCERT or the Ministry of Education -- we organise publicly available NCERT content by class and subject, verify links against official sources, and build tools (like our in-browser reader) that make studying more convenient. Every guide we publish is written and reviewed by our team based on the actual NCERT curriculum and syllabus.