Q16 of 69 Page 238

The height of an equilateral triangle measures 9 cm. Find its area, correct to 2 decimal places. Take =1.732.

Let us assume a be the side of the equilateral triangle


We know that,


Height of an equilateral triangle = a units


Height 0f the equilateral triangle = 9 cm (Given)




= (Rationalizing the denominator)


=


= 6


Base of the triangle =


We know that,


Area of triangle =


= × 6 × 9


= 27


= 27 × 1.732


= 46.76 cm2 (Up to 2 decimal places)


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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.


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