Homework panic, y7 maths

[Jux]

Reflections: y=4.

DD has a 5 sided shape on a graph and has to draw it for y=4. Does this mean she shoves it up the y axis by 4 points, so an original point being (1,3) would become (1,7) and so on?

I would say it means that it is reflected in the line y=4. To be exact this means that the line y=4 would be the line of symmetry.

You draw a horizontal line that cuts through the y-axis at 4. Then draw a reflection of the shape using that line (the equation of the line is y=4) as the mirror.

Oh, so the point (1,3) would then become (1,5) and the whole shape would be upside down?

Brilliant, thank you both. Makes complete sense when you know, like so much of maths! I'm actually a bit embarrassed as I'm doing a maths course with the OU but it's clearly so babyish that I can't find this in any of our text books! (We do quadratic equations though!)

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