we know that
the formula to calculate the distance between two points is equal to
[tex]d=\sqrt{(y2-y1)^{2}+(x2-x1)^{2}}[/tex]In this problem we have
(x1,y1)=(-10,-3)
(x2,y2)=(6,-3)
substitute in the formula
[tex]d=\sqrt{(-3+3)^2+(6+10)^2}[/tex][tex]d=\sqrt{(0)^2+(16)^2}[/tex]d=16 units
the distance is 16 units