Step-by-step explanation:
6.
90° counterclockwise.
x and y are trading places, and the new x (the original y) flips the sign.
A (-7, 0) turns into A' (0, -7). 0 does but have a sign ...
B (-12, 5) turns into B' (-5, -12).
C (-3, 5) turns into C' (-5, -3).
remember the perpendicular slope of lines ? y/x turns into -x/y. the same principle here. just here we need to pay attention to which coordinate flips the sign - depending on the clockwise/counterclockwise direction it is either the original x or y.
7.
180° counterclockwise (for 180° the direction is irrelevant, it is a half-circle, and no matter in what directing you turn the points, they end up at the same location).
both signs are flipped. that's it. 180° is 2 rotations by 90° in the same direction.
as we can see from doing 6. two times that means x and y have switched back into their original positions, but both signs have flipped.
A (-5, -2) turns into A' (5, 2).
B (-5, 3) turns into B' (5, -3).
C (0, 7) turns into C' (0, -7).
D (0, 3) turns into D' (0, -3).
