How do I extend or reduce the length of a diagonal line using VAB

I have an XL spreed***

On "sheet1" I have a basic drawing shape (a line) set at 45 degrees that I
want to change in size with respect to a value held in "sheet1" range A1

Range A1 value is changed fequently as a result of changes on other sheets
in this spreed***

I would like this line to be automatically resized relative to the value of
range A1 each time I visit "sheet1"

I am trying to produce this effect using VBA - but so far without success.

Can anyone provide me with the VBA code

Your help would be very much appreciated

Keith
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