Question

Line segment RS has endpoints R (-2, 4) and S (-4, -1).

Line segment R''S'' has endpoints R'' (3, -3) and S'' (5, 2).


Name the transformation that maps line segment RS to line segment R''S''.

Answer 1

rotation 180° (ccw) over point (0.5 , 0.5)

Explanation:

R (-2, 4) , S (-4, -1) -> R'' (3, -3) , S'' (5, 2)

check: rotation over (0.5,0.5) 180°

x'' = - (x - x₀) + x₀ .. x: original x coordinate, x₀ : center of rotation

y" = - (y - y₀) + y₀

for R" : x" = - (-2 - 0.5) + 0.5 = 3

y" = -(4 - 0.5) + 0.5 = -3

You can verify the coordinates of S" by the above formula.

** (0.5,0.5) is the intersect of RR" and SS"