Answer: 20 √2 cm or 28.3 cm
Step-by-step explanation:
Folding a paper diagonally will result in two triangles. You know each side of the square piece of paper is 20 cm, so a^2 and b^2 is 20 cm.
Use the formula ‘a^2 + b^2 = c^2’
20^2 + 20^2 = c^2
400 + 400 = 800
√800 = 20 √2 or 28.3 cm
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