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Bonsoir,
1) Figure.
2) [tex]\vec{EF}=2\vec{EC}\\\\(x_F-x_E;y_F-y_E)=2(x_C-x_E;y_C-y_E)\\\\(x_F-2;y_F+3)=2(3-2;1+3)\\\\(x_F-2;y_F+3)=2(1;4)\\\\(x_F-2;y_F+3)=(2;8)[/tex]
[tex]\left\{\begin{matrix}x_F-2=2\\ y_F+3=8\end{matrix}\right.\ \ \ \ \left\{\begin{matrix}x_F=4\\ y_F=5\end{matrix}\right\\\\\\F(4;5)[/tex]
[tex]3)\ CE=\sqrt{(x_E-x_C)^2+(y_E-y_C)^2}\\\\CE=\sqrt{(2-3)^2+(-3-1)^2}\\\\CE=\sqrt{(-1)^2+(-4)^2}\\\\CE=\sqrt{1+16}\\\\CE=\sqrt{17}[/tex]
1) Figure.
2) [tex]\vec{EF}=2\vec{EC}\\\\(x_F-x_E;y_F-y_E)=2(x_C-x_E;y_C-y_E)\\\\(x_F-2;y_F+3)=2(3-2;1+3)\\\\(x_F-2;y_F+3)=2(1;4)\\\\(x_F-2;y_F+3)=(2;8)[/tex]
[tex]\left\{\begin{matrix}x_F-2=2\\ y_F+3=8\end{matrix}\right.\ \ \ \ \left\{\begin{matrix}x_F=4\\ y_F=5\end{matrix}\right\\\\\\F(4;5)[/tex]
[tex]3)\ CE=\sqrt{(x_E-x_C)^2+(y_E-y_C)^2}\\\\CE=\sqrt{(2-3)^2+(-3-1)^2}\\\\CE=\sqrt{(-1)^2+(-4)^2}\\\\CE=\sqrt{1+16}\\\\CE=\sqrt{17}[/tex]