Question

write 21 as the difference of the squares of two consecutive natural numbers

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Answer 1

Answer:

Let X be one natural number

Next consecutive natural number :-- [ X + 1 ]

[ X + 1 ] ^ 2 — X ^ 2 = 21

2X + 1 = 21

X = 10

21 = 11^2 — 10^2

21 equals the difference between square of 11 and square of 10.