Question

The diagram shows rectangle ABCD on a pair of aces. The lengths of its sides are 20 units and 5 units. The coordinates of point A are (3,9). What are the coordinates of point C?

Answer 1

20...3,9
5.....x
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20x=5*3,9
20x=19,5
x=19,5:20
x=0,975

You can also do it like this:

20:5=4
3,9:4=0,975

I hope it's correct and it helps you. :)