Question
Evaluate:
$ 69 × 71$
$ 69 × 71$
✓
Answer
$= (70 - 1) × (70 + 1)$
$= [(70)^2- (1)^2]$
$= (4900 - 1)$
$= 4899$
$= [(70)^2- (1)^2]$
$= (4900 - 1)$
$= 4899$
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