document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152454>Question 1152454</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A triangle with vertices A(5,3), B(1,-4) and C(-3,1) is rotated 90° counterclockwise about vertex B. What are the co-ordinates of the image of vertex A? </SPAN>\n" );
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document.write( "From B to A is 4 units right and 7 units up.<br><BR>\n" );
document.write( "When the figure is rotated 90 degrees counterclockwise, the \"right\" becomes \"up\" and the \"up\" becomes \"left\".<br><BR>\n" );
document.write( "The rotation is about vertex B, so from B to the image of A is 4 units up and 7 units left.  7 units left and 4 units up from B(1,-4) is (-6,0).<br><BR>\n" );
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