Q15 of 69 Page 238

Each side of an equilateral triangle measures 8cm. Find:

(i) The area of the triangle, correct to 2 places of decimal


(ii) The height of the triangle, correct to 2 places of decimal.


Take =1.732

(i) We know that,


Area of an equilateral triangle = sq units


It is given that, each side of equilateral triangle is of 8 cm


Therefore,


Area = × 82


=


=


= 1.732 × 16


= 27.712


= 27.71 cm2 (Up to 2 decimal places)


(ii) We also know that,


Height of an equilateral triangle = a


= × 8


=


= 1.732 × 4


= 6.928


= 6.93 cm (Up to 2 decimal places)


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