A line segment has endpoints (0,5) and (6,5). After the line segment is reflected across the x-axis, how long will it be?

a 5 units
b 6 units
c 11 units
d 1 units

When a line segment is reflected across the x-axis, its y-coordinates change sign.

Therefore, the endpoints of the reflected line segment would be (0,-5) and (6,-5).

To find the length of the line segment, we can use the distance formula:

d = √((x2 - x1)^2 + (y2 - y1)^2)

Using the endpoints of the reflected line segment, we have:

d = √((6 - 0)^2 + (-5 - (-5))^2)
= √(36 + 0)
= √36
= 6

Therefore, the length of the reflected line segment is 6 units.

The correct answer is b) 6 units.