Question

9. Without actually squaring, find the value of the following:
a) 21square - 20square

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Answer 1

Answer:

21^2-20^2

(a^2-b^2) =( a +b)(a-b)

(21+20)(21-20)

(41)(1)

41

Answer 2

Answer:

41

Step-by-step explanation:

21^2 - 20^2

=(21+20)(21-20)

=41 * 1

=41