Pls help pls its rlly hard

23

Step-by-step explanation:

9514 1404 393

  (d)  √25

Step-by-step explanation:

The square root of an integer is a rational number if it is the root of a perfect square. From your knowledge of multiplication tables, you know that 25 = 5×5 is a perfect square.

  √25 = 5 is a rational number

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Additional comment

It can be useful to memorize the squares of integers up to about 20. You probably already know the first 10 or 12 from your memorization of multiplication tables.

  1² = 1, 2² = 4, 3² = 9, 4² = 16, 5² = 25, 6² = 36, 7² = 49, 8² = 64, 9² = 81,

  10² = 100, 11² = 121, 12² = 144, 13² = 169, 14² = 196, 15² = 225, 16² = 256,

  17² = 289, 18² = 324, 19² = 361, 20² = 400

45

step-by-step explanation: