[tex]endpoint: \ ( x_{2},y_{2})= (6,-10) , \\ midpoint : \(x,y)=(-1,2) \\\\Mindpoint \ Formula : \\ (x,y)=\left ( \frac{x_{1}+x_{2} }{2}, \frac{y_ {1}+y_{2} }{2} \right )\\\\(-1,2)=\left ( \frac{x_{1}+ 6 }{2}, \frac{y_ {1}-10 }{2} \right )[/tex]
[tex]\begin{cases} \frac{x_{1}+ 6 }{2}= -1 \ \ /\cdot 2 \\ \frac{y_ {1}-10 }{2} =2 \ \ / \cdot 2 \end{cases}\\\\\begin{cases} x_{1}+ 6 =-2 \\ y_ {1}-10 =4 \end{cases}\\ \\\begin{cases} x_{1} =-2-6 \\ y_ {1} =4+10 \end{cases}\\ \\\begin{cases} x_{1} =-8\\ y_ {1} =14 \end{cases} \\ \\Answer : \ second \ endpoint : \ (x_{1},y_{1})=(-8,14)[/tex]
