document.write( "Question 1166708: Perform 45degree rotation of a triangle ABC; A(0,2), B(-1, -1), C(1,-1) about the origin. \n" ); document.write( "
Algebra.Com's Answer #791222 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You did not specify whether the rotation is counter-clockwise or clockwise,\r\n" );
document.write( "so since 45° is positive, I'll assume it is a counter-clockwise rotation.\r\n" );
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document.write( "The formulas are\r\n" );
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document.write( "x' = x∙cos(θ) - y∙sin(θ)\r\n" );
document.write( "y' = x∙sin(θ) + y∙cos(θ)\r\n" );
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document.write( "I'll let you do all the substitutions.  Here's how the new triangle looks,\r\n" );
document.write( "(in green).\r\n" );
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document.write( "  \r\n" );
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document.write( "Edwin
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