Answer:
A' = (-1, 3)
B' = (-4, 0)
C' = (1, 6)
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Reason:
The notation
means "translate 3 units left, 5 units up".
Another way to write out this rule is

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Let's apply that rule to the coordinates of point A.

Point A' is located at (-1, 3)
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Repeat for the coordinates of point B.

Point B' is located at (-4, 0)
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Lastly do the same for point C.

Point C' is located at (1, 6)