9514 1404 393
Answer:
(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
__
<em>Additional comment</em>
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
