Which transformation would change the point (5,3) into (-5,3)?

A transformation like this would be a reflection across the Y access. If you flip this point about the Y access, the Y will not change but you will get the inverse of the X.
Hope this helps! :D

If you need an equation, it would be y=2x+8, y would be how long it grew, x being weeks.if you need how long he was asleep, it would be 4 weeks if he started with no beard, the equation would be x=8÷2if he did have a beard before hand, the equation would be 2w+x=8