Acircle has diameter 11 cm a square had side length 7 cm use pythagoras' theorem to show that the square will fit inside the circle without touching the edge of the circle. , !

By the Pythagorean theorem, the diagonal length (d) of the square is
  d² = 7² + 7²
  d = √98 ≈ 9.8995

Since the diameter of the circle (11 cm) is greater than the diagonal length of the square (9.9 cm), you know the square will fit into the circle without touching.

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You can also draw it.