Let $a = 4 + 3i,$ $b = 1 -2i,$ and $c = 8 - 5i.$  The complex number $d$ is such that $a,$ $b,$ $c,$ and $d$ form the vertices of a parallelogram, when plotted in the complex plane.  Enter all possible values of $d,$ separated by commas.
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Let $a = 4 + 3i,$ $b = 1 -2i,$ and $c = 8 - 5i.$  The complex number $d$ is such that $a,$ $b,$ $c,$ and $d$ form the vertices of a parallelogram, when plotted in the complex plane.  Enter all possible values of $d,$ separated by commas.
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user
-3 + 6i
Let $a = 4 + 3i,$ $b = 1 -2i,$ and $c = 8 - 5i.$  The complex number $d$ is such that $a,$ $b,$ $c,$ and $d$ form the vertices of a parallelogram, when plotted in the complex plane.  Enter all possible values of $d,$ separated by commas.
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