Question
Evaluate:
$78 × 82$
$78 × 82$
✓
Answer
$= (80 - 2) × (80 + 2)$
$= [(80)^2- (2)^2]$
$= (6400 - 4)$
$= 6396$
$= [(80)^2- (2)^2]$
$= (6400 - 4)$
$= 6396$
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