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
[tex]A(4,-1)\\B(9,7[/tex]
substitute the values
[tex]d=\sqrt{(7+1)^{2}+(9-4)^{2}}[/tex]
[tex]d=\sqrt{(8)^{2}+(5)^{2}}[/tex]
[tex]d=\sqrt{89}\ units[/tex]
[tex]d=9.43\ units[/tex]
therefore
the answer is
[tex]9.43\ units[/tex]
