Question

Reflect triangle X'Y'Z' over the line y=1
X'=(-11,13), Y'=(-14,17), Z'=(-16,14)

Answer 1

The y-coordinate of the first point is 13.
y-coordinate of 13 is 12 units ABOVE the line y = 1.
When we reflect it over the line y = 1, it will be 12 units BELOW the line y = 1 which makes it 1 - 12 = -11.
So reflection of X' (-11,13) over the line y = 1 is (-11, -11).

You can do the rest the same way.

Answer 2

what are the coordinates for X'', Y',' Z''

Answer 3

I showed you above X'' = (-11,-11)

Do Y'' and Z'' the same way I did X''.

The x-coordinate of the point will not change when reflecting over the line y=1.
Only the y-coordinate will change.

A point (a,b) when reflected over the line y = 1 will change to (a, 2-b)
because b is (b-1) above the line y = 1
when reflected, it will be (b-1) below the line. That is, 1 - (b-1) = 1 - b + 1 = 2-b