RS Aggarwal Class 8 Math Eighteenth Chapter Area of a Trapezium and a Polygon Exercise 18B Solution
EXERCISE 18B
(1) In the given figure, ABCD is a quadrilateral in which AC = 24 cm, BL ⊥ AC and DM ⊥ AC such that BL = 8 cm and DM = 7 cm. Find the area of quad. ABCD.
Solution: Area of quad. ABCD = ar (∆ADC) + ar (∆ABC)
(2) In the given figure, ABCD is a quadrilateral – shaped field in which diagonal BD is 36 m, AL ⊥ BD and CM ⊥ BD such that AL = 19 m and CM = 11m. Find the area of the field.
Solution: Area of the field ABCD = ar (∆ ABD) + ar (∆ BCD)
(3) Find the area of pentagon ABCDE in which BL ⊥ AC, DM ⊥ AC and EN ⊥ AC and FP ⊥ AD such that AC = 18 cm, AM = 14 cm, AN = 6 cm, BL = 4 cm, DM = 12 cm and EN = 9 cm.
Solution: Area of the given pentagon ABCDE
= ar (∆AEN) + ar (trap. EDMN) + ar (∆DCM) + ar (∆ACE)
(4) Find the area of hexagon ABCDEF in which BL ⊥ AD, CM ⊥ AD, EN ⊥ AD and FP ⊥ AD such that AP = 6 cm, PL = 2 cm, LN = 8 cm, NM = 2 cm, MD = 3 cm, FP = 8 cm, EN = 12 cm, BL = 8 cm and CM = 6 cm.
Solution: Area of hexagon ABCDEF,
= ar (∆AFP) + ar (trap. EFNP) + ar (∆DEN) + ar (∆ ABL) + ar (trap. BCLM) + ar (∆DCM)
(5) Find the area of pentagon ABCDE in which BL ⊥ AC, CM ⊥ AD and EN ⊥ AD such that AC = 10 cm, AD = 12 cm, BL = 3 cm, CM = 7 cm and EN = 5cm.
(6) Find the area enclosed by the given figure ABCDEF as per dimensions given herewith.
(7) Find the area of given figure ABCDEFGH as per dimensions given in it.
(8) Find the area of regular hexagon ABCDEF in which each side measures 13 cm and whose height is 23 cm, as shown in the given figure.
