Answer: 180 degrees
note: it doesn't matter if its clockwise or counterclockwise when it comes to 180 degree rotations.
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Explanation:
The rule for 180 degree rotations is
(x,y) ---> (-x, -y)
So the x and y coordinates flip in sign from positive to negative, or vice versa.
Point D ' (-3, 5) rotates to D ' (3, -5) following this rule
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A further detailed break down might look like this
x = -3 becomes -x = -(-3) = 3
y = 5 becomes -y = -5
(-3, 5) ----> (3, -5)
