Pls me, i answered 1 but it’s not right

AB=4.5

Explanation:

You have to use the formula they give you down below.

The coordinates of A are (3,1) and the coordinates for B are (-1,-1).

Then to plug it into the formula, this would be what you use: x1=3, x2= -1, y1=1, y2= -1. Plugging it into the formula should look like this:

Simplify and you get √(-4)²+(-2)². Use the square roots and you get √16+4, or √20. √20 in decimal form rounds to 4.5.

Hope this helps!