Question in image please help quickly, I'm on a time limit :D

Answer:
By distance formula ,
[tex]AB = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}[/tex]
[tex]AB = \sqrt{(-1-5)^2 + (6-3)^2}[/tex]
[tex]AB = \sqrt{36 + 9}[/tex]
[tex]AB = \sqrt{45}[/tex]
[tex]AB = 6.708[/tex](approx)
To give answer in 3 significant figures :
AB = 6.70