Translation of 10 units left and 8 units down
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Explanation:
Always start with the preimage. Let's say we focus on point A located at (3,6). Its corresponding point is A' located at (-7,-2). To go from (3,6) to (-7,-2), we move 10 units to the left and 8 units down.
The motion "10 units to the left" means we subtract 10 from the x coordinate. The "8 units down" part means we subtract 8 from the y coordinate.
Overall, the translation rule is
If we applied that rule to A(3,6), then...
which is what the diagram shows going from A to A'
Let's do the same for point B(3,1)
This indicates B(3,1) moves to B ' (-7,-7) which is what the diagram shows. I'll let you confirm that C(6,6) moves to C ' (-4,-2) using that translation rule.