document.write( "Question 1011927: please help me solve this question\r
\n" ); document.write( "\n" ); document.write( "The vertices of a triangle are (1,a)(2,b)(c square,-3):-
\n" ); document.write( "(1) Prove that its centroid cannot lie on the Y - axis.
\n" ); document.write( "(2) Find the condition that the centroid may lie on the X - axis
\n" ); document.write( "

Algebra.Com's Answer #627799 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
(1) The centroid of a convex polygon is inside the polygon.
\n" ); document.write( "Since The x-coordinates of A, B, and C are all positive number,
\n" ); document.write( "so will be the x-coordinate of the centroid,
\n" ); document.write( "meaning that it will lie to the right of the y-axis.
\n" ); document.write( "Another way;
\n" ); document.write( "The x-coordinate of the centroid is the average of the x-coordinates of the vertices,
\n" ); document.write( "so it is \"%281%2B2%2Bc%5E2%29%2F3=%283%2Bc%5E2%29%2F3=1%2Bc%5E2%2F3%3E=1\" ,
\n" ); document.write( "so the centroid lies on the line \"x=1\" or to its right,
\n" ); document.write( "at a distance of at least \"1\" to the right of the y-axis.
\n" ); document.write( "
\n" ); document.write( "(2) The y-coordinate of the centroid is the average of the y-coordinates of the vertices,
\n" ); document.write( "so it is \"%28a%2Bb-3%29%2F3\" .
\n" ); document.write( "For the centroid to be on the x-axis, that y-coordinate must be zero:
\n" ); document.write( "\"%28a%2Bb-3%29%2F3=0\"<-->\"a%2Bb-3=0\"<-->\"highlight%28a%2Bb=3%29\" .
\n" ); document.write( "
\n" );