Let two ordinate of the other end R be Y Coordinates of other end R are (10,y) i.e., R(10,y)

Distance PR=10 [given]

Squaring both sides

⇒ 100=73+y^{2}+6y

⇒ y^{2}+6y+73-100=0

⇒ y^{2}+6y-27=0

Splitting the middle term

⇒ y^{2}+9y-3y-27=0

⇒ y(y+9)-3(y+9)=0

⇒ (y+9)(y-3)=0

⇒ y= -9, y=3