Question
Using suitable identities, evaluate the following.
$(69.3)^2-(30.7)^2$
$(69.3)^2-(30.7)^2$
✓
Answer
$(69.3)^2-(30.7)^2$
$= (69.3 + 30.7)(69.3 - 30.7)$
$= 100 \times 38.6$
$= 3860$
$= (69.3 + 30.7)(69.3 - 30.7)$
$= 100 \times 38.6$
$= 3860$
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