The approximate width of Alice's backyard is 22.36 in.
Let l be the length of the rectangle and w be the width.
l = 2w
A = 1000 m2 = l*w
1000 m2 = 2w *w
500 m2 = w^2
√500 m2 = √w^2
w = 22.360679775 in or 22.36 in
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