document.write( "Question 200996This question is from textbook geometry
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document.write( ": can you please help me solve(((What is the area of an equilateral triangle with perimeter 12? ))) \n" );
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Algebra.Com's Answer #151235 by RAY100(1637)![]() ![]() ![]() You can put this solution on YOUR website! Remember,, equilateral triangle,, sides same,,,, \n" ); document.write( ". \n" ); document.write( "Perimeter = sum of sides = s+s+s = 3s =12,,,,s=4 \n" ); document.write( ". \n" ); document.write( "With s=3, we could use Herons Formula ,, but just as easy to resolve. \n" ); document.write( ". \n" ); document.write( "Area = 1/2 * base * height \n" ); document.write( ". \n" ); document.write( "Height is perpendicular to base, therefore c^2 = a^2 + b^2.( use rough sketch) \n" ); document.write( ". \n" ); document.write( "in our case,,,c= 4,,,,a=2,,,,therefore c= 3.46,,,which is height \n" ); document.write( ". \n" ); document.write( "Area = 1/2 * 4 * 3.46 = 6.93 \n" ); document.write( ". \n" ); document.write( "Check,,,rough sketch shown height to vertex makes a 30-60-90 triangle, with sides 1 - 2 - sqrt3,, \n" ); document.write( "with leg 2 and hypotenuse 4, therefore other leg is 2(sqrt3) {height}, \n" ); document.write( "and area is 1/2 * 4* 2sqrt3 = 4 sqrt3 = 6.93,,,ok \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( " |