document.write( "Question 959109: A triangle has coordinates of (1,1), (4,1), and (3,4). is it a 30-60-90 triangle and why? \n" ); document.write( "
Algebra.Com's Answer #586203 by MathLover1(20855)\"\" \"About 
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THERE ARE TWO special triangles in trigonometry. One is the \"30\"°-\"60\"°-\"90\"° triangle. The other is the \"isosceles\"\"+right\"\"+triangle\". They are special because, with simple geometry, we can know the ratios of their sides.\r
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\n" ); document.write( "\n" ); document.write( "so, what we need to do first is find the sides length using given points and distance formula\r
\n" ); document.write( "\n" ); document.write( "(1,1), (4,1), and (3,4)\r
\n" ); document.write( "\n" ); document.write( "the distance between (1,1)and (4,1) \r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%28%284-1%29%5E2%2B%281-1%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%283%5E2%2B0%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%283%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=3\"\r
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\n" ); document.write( "\n" ); document.write( "the distance between (1,1)and (3,4) \r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%28%283-1%29%5E2%2B%284-1%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%282%5E2%2B3%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%2813%29\"-exactly\r
\n" ); document.write( "\n" ); document.write( "\"d=3.6\"-approximately\r
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\n" ); document.write( "\n" ); document.write( "the distance between (4,1) and (3,4)\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%28%284-3%29%5E2%2B%281-4%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%281%5E2%2B%28-3%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"d=sqrt%2810%29\"-exactly\r
\n" ); document.write( "\n" ); document.write( "\"d=3.2\"-approximately\r
\n" ); document.write( "\n" ); document.write( "so, the shortest side is \"3\" units long, then the longer side is \"sqrt%2810%29\" and the longest side is \"sqrt%2813%29\" \r
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\n" ); document.write( "\n" ); document.write( "now, check if these are sides of a \"30\"°-\"60\"°-\"90\"° triangle\r
\n" ); document.write( "\n" ); document.write( "first, use Pythagorean theorem because triangle has an \"90\"° angle\r
\n" ); document.write( "\n" ); document.write( "\"%28sqrt%2813%29%29%5E2=%28sqrt%2810%29%29%5E2%2B3%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"13=10%2B9\"\r
\n" ); document.write( "\n" ); document.write( "\"13%3C%3E19\"=>your triangle is not a \"30\"°-\"60\"°-\"90\"° triangle\r
\n" ); document.write( "\n" ); document.write( "other way is to use a theorem: \r
\n" ); document.write( "\n" ); document.write( " In a \"30\"°-\"60\"°-\"90\"° triangle the sides are in the ratio \"1+%3A+2+%3A+sqrt%28+3%29\".\r
\n" ); document.write( "\n" ); document.write( "now, the sides of this triangle are in ratio \"3%3Asqrt%2810%29%3Asqrt%2813%29\" \r
\n" ); document.write( "\n" ); document.write( "compared to \"1+%3A+2+%3A+sqrt%28+3%29\", we can see that these ratios are not equivalent; so, your triangle is not a
\n" ); document.write( "\"30\"°-\"60\"°-\"90\"° triangle \r
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\n" ); document.write( "\n" ); document.write( "now, see it on a graph:\r
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