Mensuration formulas Part-1

1.     Rectangle:

·        Area= l×b

·        Perimeter= 2(l+b)

·        Diagonal= √(l²+b²)

      2.     Square:

·        Area= a²

·        Perimeter= 4a

·        Diagonal= a√2

      3.     Triangle:

·        s=(a+b+c)/2

Area = √[s(s-a)(s-b)(s-c)]

·        Perimeter= a+b+c

      4.     Right angle triangle:

·        Area = b×h/2

·        (AC)²=(AB)²+(CA)²

·        Perimeter= Sum of all sides

      5.     Equilateral triangle:

·        h=√3×a/2

·        Area = √3×a²/4

·        Perimeter= 3a

       6.     Isosceles triangle:

·        h=√(4a²-b²)×1/2

·        Area = b/4×√(4a²-b²)

·        Perimeter= a+a+b

      7.     Isosceles right angle triangle:

·        Area = a²/2

·        Perimeter= Sum of all sides

      8.     Parallelogram:

·        Area= h×b

·        Perimeter= 2(a+b)

      9.     Rhombus:

·        Area = ½ d₁d₂

·        Perimeter= 4a

·        ∠AOB= ∠ BOC= ∠COD= ∠DOA=90˚

      10.  Trapezium:

·        Area = ½(a+b)h