document.write( "Question 1013118: Geometry: Triangles
\n" ); document.write( "if triangle MNP, MN= 4x+1, Np+7x-11, and MP= 11x-16. If the perimeter of triangle MNP is 84, order the angles from greatest. I need help please! \n" ); document.write( "
Algebra.Com's Answer #629281 by Boreal(15235)\"\" \"About 
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4x+1+7x-11+11x-16=84
\n" ); document.write( "22x-26=84
\n" ); document.write( "22x=110
\n" ); document.write( "x=5
\n" ); document.write( "It helps to draw this. I have MN as the base and P to the upper right of N. Angle A is P, angle B is M, angle C is N. Law of Cosines
\n" ); document.write( "MN is 21 (A)
\n" ); document.write( "NP=24 (B)
\n" ); document.write( "MP=39 C) C will be the biggest angle
\n" ); document.write( "c^2=a^2+b^2-2abcosC
\n" ); document.write( "1521=441+576-2(504) cos C
\n" ); document.write( "504=-2(504)cos C
\n" ); document.write( "cos C=-(1/2)=120 degrees.
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\n" ); document.write( "a^2=b^2+c^2-2bc cos A
\n" ); document.write( "441=576+1521-2(936) cos A
\n" ); document.write( "-1656= -1872 cos A
\n" ); document.write( "cos A=27.8 degrees Can assume the other angle is 32.2 but will check to be sure.
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\n" ); document.write( "b^2=a^2+c^2-2ac cos B
\n" ); document.write( "576=441+1521-2(819) cos B
\n" ); document.write( "-1386=-1638 cos B
\n" ); document.write( "cos B=32.2
\n" ); document.write( "The angle at N is the largest, the one at M the second largest, and the one at P the smallest.
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