Using the formula for squaring a binomial, evaluate the following… - Vidyadip

Question

Using the formula for squaring a binomial, evaluate the following:
$(78)^2$

✓

Answer

$(78)^2$
$= (80 - 2)^2$
$= (80)^2- 2 × 80 × 2 + (2)^2$
$= 6400 - 320 + 4$
$= 6404 - 320$
$= 6084$

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