Using 42 = 40 + 2, the square of 42 is:
A1764
B1684
C1604
D1744
Answer & Solution
Correct answer: A. 1764
1. 40 squared is 1600.
2. Add 80 + 80 + 4.
3. That gives 1764.
_Source: NCERT Class 8 Mathematics, Chapter 6, Squares and Square Roots._
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