[tex]\\ \sf\longmapsto P(x,y)=\left(\dfrac{mx_2+nx_1}{m+n},\dfrac{my_2+ny_1}{m+n}\right)[/tex]
[tex]\\ \sf\longmapsto P(x,y)=\left(\dfrac{(1)(-14)+(4)(-3)}{1+4},\dfrac{(1)(7)+(4)(6)}{1+4}\right)[/tex]
[tex]\\ \sf\longmapsto P(x,y)=\left(\dfrac{-26}{5},\dfrac{31}{5}\right)[/tex]