Answer:
As we know rectangles have 90 degree angles at all 4 of its corners.
In this question we know that the length is 4 feet while the bredth is 3 feet.
Therefore to solve this answer we can use the Pythagoras theorm.
By Pythagoras:
Therefore the diagonal must be 5 feet
So if Luisa measures the diagonal with a tape and it measures 5
Then it proves that all 4 corners due have 90 degree angles
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