Archive
7th of September 2015
Mathematics
Q:

using heron's formula,find the area of equilateral triangle with side 12 cm

Sacheta Saini - CBSE - Class IX

Saturday, September 05, 2015 at 20:02:PM

A:

begin mathsize 16px style S i d e space o f space a n space e q u i l a t e r a l space t r i a n g l e space equals space 12 space c m H e r o n apostrophe s space f o r m u l a equals square root of s left parenthesis s minus a right parenthesis left parenthesis s minus b right parenthesis left parenthesis s minus c end root a comma b comma c space a r e space s i d e s space o f space e q u i l a t e r a l space t r i a n g l e. s equals s e m i minus p e r i m e t e r equals fraction numerator a plus b plus c over denominator 2 end fraction equals fraction numerator 12 plus 12 plus 12 over denominator 2 end fraction equals 18 space c m A r e a equals square root of 18 left parenthesis 18 minus 12 right parenthesis left parenthesis 18 minus 12 right parenthesis left parenthesis 18 minus 12 right parenthesis end root equals square root of 18 cross times 6 cross times 6 cross times 6 end root equals square root of 3 cross times 6 cross times 6 cross times 6 cross times 6 end root equals 36 square root of 3 space s q. space c m end style

Monday, September 07, 2015 at 18:04:PM