document.write( "Question 497455: 1.the area of the triangle with sides 36 meters, 54 meters, 77 meters?
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document.write( "2.two m16 rifles are stock to the ground. the first rifle is 99 cm in length while the other is attached to a bayonet knife having length of 112 cm if the angle formed by two rifles is 50 degrees, determine the distance between the butt plates of the rifles. \n" );
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Algebra.Com's Answer #336737 by Theo(13342) You can put this solution on YOUR website! you can use heron's formula to find the area of the triangle when given 3 sides.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "heron's formula is: \n" ); document.write( "a = sqrt(s(s-a)(s-b)(s-c)) where: \n" ); document.write( "a = area \n" ); document.write( "s = (a + b + c)/2 \n" ); document.write( "s can also be shown as p/2 where: \n" ); document.write( "p = a + b + c\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in your triangle: \n" ); document.write( "a = 36 \n" ); document.write( "b = 54 \n" ); document.write( "c = 77\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "using heron's formula, we get: \n" ); document.write( "p = a + b + c = 167 \n" ); document.write( "p/2 = 167/2 = 83.5 \n" ); document.write( "a = sqrt(s(s-a)*(s-b)*s-c)) becomes: \n" ); document.write( "a = sqrt(83.5(47.5)(29.5)(6.5)) which becomes: \n" ); document.write( "a = 872.0828157\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's a solver from one of the folks at algebra.com that give you the answer with a lot less effort on your part. \n" ); document.write( "http://www.algebra.com/algebra/homework/Triangles/Find-the-area-of-triangle-if-3-sides-are-given.solver\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "it's good to know the formula though. \n" ); document.write( "on a test, you won't have access to the nifty little tool developed here. \n" ); document.write( "best thing is to do the calculations yourself and then use the tool to check your work.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you could also have solved for the area using the law of cosines but it's a lot more work. \n" ); document.write( "kudos to heron.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your second problem is different because you are given an angle. \n" ); document.write( "assume your triangle is labeled ABC. \n" ); document.write( "The angle that is 50 degrees would be A. \n" ); document.write( "The side that is 99 cm in length would be AB. \n" ); document.write( "The side that is 112 cm in length would be AC. \n" ); document.write( "BC is the side opposite angle A, the length of which is unknown.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you want to find the length of BC which is the distance between the butts of each rifle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you can use the law of cosines here. \n" ); document.write( "re-label your triangle as follows: \n" ); document.write( "AB = c \n" ); document.write( "AC = b \n" ); document.write( "BC = a \n" ); document.write( "AB is opposite angle C which means that c is opposite angle C \n" ); document.write( "AC is opposite angle B which means that b is opposite angle B \n" ); document.write( "BC is opposite angle A which means that a is opposite angle A\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the law of cosines states:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a^2 = b^2 + c^2 - 2*b*c*cos(A)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "substitute known values into this formula to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a^2 = 112^2 + 99^2 - 2*112*99*cos(50) which becomes: \n" ); document.write( "a^2 = 12544 + 9801 - 22176*.64278761 which becomes: \n" ); document.write( "a^2 = 8090.541968 \n" ); document.write( "take square root of both sides of this equation to get: \n" ); document.write( "a = 89.94744003\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your triangles look like this:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |