document.write( "Question 1159866: Determine the area of the right triangle with vertices R(4,4), S(-2,-2), and T(10,-2). \n" ); document.write( "

Algebra.Com's Answer #782974 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
Determine the area of the right triangle with vertices R(4,4), S(-2,-2), and T(10,-2).
\n" ); document.write( "===========
\n" ); document.write( "Another method:
\n" ); document.write( "

\r\n" );
document.write( "   R   S   T   R\r\n" );
document.write( "x  4  -2  10   4\r\n" );
document.write( "y  4  -2  -2   4\r\n" );
document.write( "

\n" ); document.write( "----------------
\n" ); document.write( "Add the diagonal products starting at the upper left:
\n" ); document.write( "--> 4*(-2) + -2*-2 + 10*4 = -8 + 4 + 40 = 36
\n" ); document.write( "----
\n" ); document.write( "Add the diagonal products starting at the lower left:
\n" ); document.write( "--> 4*-2 + -2*10 + -2*4 = -8 -20 - 8 = -36
\n" ); document.write( "The difference is 72.
\n" ); document.write( "The area is 1/2 that, = 36 sq units.
\n" ); document.write( "=======================
\n" ); document.write( "Might be the \"hard way\" for a triangle, but it works for any plane figure, with any # of sides.
\n" ); document.write( "The points must be entered in order around the figure is the only restriction.\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );