Using the formula for squaring a binomial, evaluate the (69)2.

1.	Using the formula for squaring a binomial, evaluate the (69)2.
Answer» Given (69)² But we can write 69 as 70-1 And also we know that (a – b)²= a²-2ab+b² By applying the above identity we get (69)²= (70-1)²= 70²-2(70) (1) +1² (70-1)²=4900-140+1=4761

Answer»

Given (69)²

But we can write 69 as 70-1

And also we know that (a – b)²= a²-2ab+b²

By applying the above identity we get

(69)²= (70-1)²= 70²-2(70) (1) +1²

(70-1)²=4900-140+1=4761

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