Question 21
A corner of a square handkerchief is folded inward as shown. The original square’s area and the area of its footprint after folding are consecutive even natural numbers, in square centimetres. Find the original area.
Figure clarification for this practice version: the fold joins the midpoints of two adjacent sides, consistent with the half-side corner shown in the illustration. The original picture did not mark those midpoints explicitly; the answer below uses this stated condition.
Figure clarification for this practice version: the fold joins the midpoints of two adjacent sides, consistent with the half-side corner shown in the illustration. The original picture did not mark those midpoints explicitly; the answer below uses this stated condition.