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Coordinates of the image after a 180 degree clockwise rotation for A B C

Coordinates of the image after a 180 degree clockwise rotation for A B C-example-1
User ThisIsTheFoxe
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1 Answer

27 votes
27 votes

A clockwise rotation is given by:


\begin{gathered} x^(\prime)=x\cos (\theta)+y\sin (\theta) \\ y^(\prime)=-x\sin (\theta)+y\cos (\theta) \end{gathered}

so:


\begin{gathered} x^(\prime)=x\cos (180)+y\sin (180)=-x \\ y^(\prime)=-x\sin (\theta)+y\cos (\theta)=-y \end{gathered}

Therefore:


\begin{gathered} A(2,2)\to(-x,-y)\to A^(\prime)(-2,-2) \\ B(3,-2)\to(-x,-y)\to B^(\prime)(-3,2) \\ C(-1,3)\to(-x,-y)\to C^(\prime)(1,-3) \end{gathered}

User Francois Nadeau
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